CHAPTER 1

INTRODUCTION

1.0 ABSTRACT

This report covered on Global Positioning System (GPS) measurements that have been
involved procedure and processing using GPS instruments and computer software. The GPS
control survey involved work of network test, baseline test, comparison on condition of GPS
instruments capability and benchmark transfer heighting. in processing scope, we are using
three different computer software such as GNSS Solution for process data from Z-Max
Magellan, Leica SKI-Pro to process data from Leica Receiver and Topcon Tools to process
data from Topcon Receiver. With producing the report, it can helps the student capability in
handling the GPS equipments and processing the satellite data to used in the future because
certain GPS knowledge cannot be found int the class.

1.1 INTRODUCTION

In advanced technology, the Global Positioning System (GPS) can be used in this determine
the X, Y, Z-value. From this, GPS can produce 3D surveying measurements and
positioning technique for the solution of the precise positioning problems. GPS
measurement can produce vertical control network by application of leveling measurements.
GPS also used to establish precise relative positions in three-dimensional and earth-centered
coordinate system. GPS carrier phase measurements are used to determine vector base lines
in space, where the components of the base line are expressed in terms of Cartesian
coordinate differences (∆ x, ∆ y and ∆ z). The vector base line can be converted to distance,
azimuth, and ellipsoidal height difference (dh), relative to a defined reference ellipsoid.

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 The result from this GPS leveling is the tests clearly view that GPS survey methods could
replace classical horizontal control terrestrial survey methods. However, there was a
problem to obtaining sufficiently accurate geoid heights; to convert GPS-derived ellipsoid
height differences to accurate GPS derived orthometric height differences. The interest in
obtaining accurate GPS-derived orthometric heights has increased in the last decade.

It is importantly to transform the ellipsoidal heights to orthometric heights; the procedure is

managed with the fundamental mathematical relationship between the two height systems.
The application of GPS for providing height control in a study area with existing leveling
data may combine the tasks of local geoid determination and its bias with the local leveling
datum. In determination of orthometric heights with GPS, the accuracy of vertical
positioning changes depending on the formula 12√K; here K is distance in kilometer,
application type and quality of the project. It is known that the surveyor especially to
constitute and densification of the vertical geodetic networks, traversing and similar
applications use several methods and technique.

1.2 AIM
The aim of this project is to perform network test between GPS station monuments,
conducting the good baseline test, comparison checking on GPS equipments capability and
transfer control and heighting on selected benchmark.

1.3 OBJECTIVE
a) To expose student knowledge and ability in conducting GPS equipments.

b) To find and solve the comparison coordinate values of each GPS monuments between
JUPEM values and observation values.

c) To understand and learning procedures in processing the data using Leica SKI-Pro,
Topcon Tools and GNSS Solutions.

d) To perform and analysis the result in data processing.

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1.4 STUDY AREA

LUBUK CINA TEBONG

TG. BIDARA
(photogrammetry)

KLEBANG
(hydrography) KOLEJ UiTM
(engineering)

BUKIT CINA
TG. KELING

1.5 THEORITICAL

The Global Positioning System (GPS) is a satellite-based navigation system made up of a

network of 24 satellites placed into orbit by the U.S. Department of Defense. GPS was
originally intended for military applications, but in the 1980s, the government made the
system available for civilian use. GPS works in any weather conditions, anywhere in the
world, 24 hours a day. There are no subscription fees or setup charges to use GPS.

There are four (4) segments of GPS configuration:

1. the Space Segment, which includes the constellation of GPS satellites, which
transmit the signals to the user;
2. the Control Segment, which is responsible for the monitoring and operation of the
Space Segment,

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3. the User Segment, which includes user hardware and processing software for
positioning, navigation, and timing applications;
4. the Ground Segment, which includes civilian tracking networks that provide the
User Segment with reference control, precise ephemerides, and real time services
(DGPS).

1) The space segment

consists of 24 satellites operating in six orbital planes spaced at 600 intervals around the
equator. Four additional satellites are held in reserve as spares. The orbital plane is
inclined to the equator at 550. This configuration provides 24- hours’ satellite coverage
between the latitudes of 800 N and 800 S. Individual satellites are normally identified by
their Pseudo Random Noise (PRN) number, but can also be identified by their satellites
vehicle number (SVN) or orbital position. Precise atomic clocks are used in the GPS
satellite to control the timing of the signals they transmit. These are extremely accurate
clocks and extremely expensive as well. The clocks in the receivers are controlled by the
oscillations of quartz, which although also precise, are less accurate than atomic clocks.

2) The control segment

Consists of five monitoring station at Colorado Spring, and on the island of Hawaii
Ascension, Diego Garcia and Kwajalein. At these station the signal from the satellite are
monitored and their orbits tracked. The master uses this data to make precise near future
precise near future prediction of satellites and their clock parameter. This information us
uploaded to the satellite and the in turn transmitted by the as a part of their broadcast
messages to be used by receiver to predict satellite position and their clock biases

(systematic error)

3) The user segment

consists of two categories of receivers that are classified by their access to two services
that the system provides. These services are referred to as the Standard Positions Service
(SPS) and the Precise Positioning Service (PPS).

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 The SPF is provided on the L1 broadcast frequency at no cost to the user, and was
intended to provide accuracies of 100 m in horizontal positions, and 156 m in vertical
positions at the 95% error level. The PPS is broadcast on both the L1 and L2 frequency
and is only available to receivers.

1.5.1 How GPS works

Global Positioning System satellites transmit signals to equipment on the ground. GPS
receivers passively receive satellite signals; they do not transmit. GPS receivers require
an unobstructed view of the sky, so they are used only outdoors and they often do not
perform well within forested areas or near tall buildings. GPS operations depend on a
very accurate time reference, which is provided by atomic clocks at the U.S. Naval
Observatory. Each GPS satellite has atomic clocks on board.

Each GPS satellite transmits data that indicates its location and the current time. All
GPS satellites synchronize operations so that these repeating signals are transmitted at
the same instant. The signals, moving at the speed of light, arrive at a GPS receiver at
slightly different times because some satellites are farther away than others. The
distance to the GPS satellites can be determined by estimating the amount of time it
takes for their signals to reach the receiver. When the receiver estimates the distance to
at least four GPS satellites, it can calculate its position in three dimensions.

1.5.2 Determining Position using GPS

For the determination of its position on earth, the GPS receiver compares the time when
the signal was sent by the satellite with the time the signal was received. From this time
difference the distance between receiver and satellite can be calculated. If data from
other satellites are taken into account, the present position can be calculated by
trilateration (meaning the determination of a distance from three points). This means
that at least three satellites are required to determine the position of the GPS receiver on
the earth surface.

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 The calculation of a position from 3 satellite signals is called 2D-position fix (two-
dimensional position determination). It is only two dimensional because the receiver
has to assume that it is located on the earth surface (on a plane two-dimensional
surface). By means of four or more satellites, an absolute position in a three
dimensional space can be determined. A 3D-position fix also gives the height above the
earth surface as a result.

1.5.3 Method of Measurement using GPS

For this project, we only use static observation.

Static surveying is high precision method developed for GPS and is the standard GPS
method for determining the length of baseline that is longer than 20km. The reference
receiver is located at a known control point and a rover is set up at a point whose
coordinates is going to determine. Both receivers generally install in tripod mounted
but it could be on a pillar.

They collect data simultaneously during a survey which must be to at least four
common satellites and which can be up to several hours duration. The observation
time depend on the accuracy required and this varies according to the type of receiver
used and the number of satellite observed, together with their geometry length of the
baseline.

Generally, as the distance between the reference and rover increases, the observation
times must also increase to maintain precision. As a guide, with more than four
satellite and good DOP, an observation time of 30 minutes for a 50 km baseline will
give a coordinate precision of around 100 mm horizontally and around twice this for
height. After one hour the precision will be 50 mm and four hours may be required
for a precision of 20 mm.

The reason why a relatively long observation period is needed is to allow the satellite
geometry to change sufficiently do that enough data is available to resolve integer
ambiguities and allow systematic errors to be removed. Single and dual frequency
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 receivers can use for static surveys, but the occupation times it generally much longer
for single frequency receivers.

The receivers collect the data over long time observation. Consequently, huge amount
of data will recorded that course a problem. In all GPS receiver contain a function on
record the data at intervals known as “epoch rates”. For static surveys, data usually
collected with an epoch rate of 10 or 15 seconds. All the data collected is post
processed to give the baseline vector components between the reference receiver and
rover.

Baseline processed by using triple differences first to remove and cycle slips followed
by double differences on the carrier phase measurements. Statistical methods are used
to solve the integer ambiguities .For best result as many errors as possible should be
removed from the observations.

1.6 GANTT CHART

Day 1 2 3 4 5 6 7 8 9 10 11 12 13 4
Date( JUNE 2011 ) 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Briefing
Test instruments
Reconnaissance
Network test
Baseline test
Data processing
GPS heighting
Report writing
Report submittion
Viva
Table 1.1: Gantt Chart

7
1.7 DIARY

8 JUN 2011

Activity : Briefing

Students Registration at Tun Mutahir College

Briefing to all part student
Part 6 student separate to two groups Group A – Photogrammetry and Group B – GPS.
Briefing about the task need to be done.

9 JUN 2011

Activity: 1st day - Test Instruments.

Test and learn the three types GPS instrument that are Topcon, Leica, and Magellan( Z-
Max)
Instrument test was done in order to familiarize and able all group members to use the
GPS instrument for easy to observation task.
All students configure the instruments.
All students go to recce and to find the location to do GPS work and to check the
condition the GPS monuments. The location is Bukit China, Tebong Tanjung Kling,
and Lubuk China.
Sketch the location roughly.

10 JUN 2011

Activity : 2nd day - Reconnaissance

Test and practice the GPS instruments that are Topcon, Leica and Magellan.
Identify the instruments that are in functionality or not.
Identify the problem of each GPS Instruments to be preparing in site work.
List the GPS instruments that are can be used.
Night class to learn about GPS software and separate to small group
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11 JUN 2011

Activity : 3rd day - Network Test 1 : Bukit China

The first GPS observation set up Bukit China by Using Magellan Z- MAX.
Setup the GPS instruments at the monument.
Record the observation in 3 hours common data.

12 JUN 2011

Activity : 4th day – Network Test 2 : UiTM Kolej Bandaraya Melaka

The next GPS observation is at Tun Mutakhir College by using Leica

Setup the GPS instruments at the point.
Record the observation in 3 hours common data.
The Leica GPS instrument have battery problem and need to be monitor frequently.

13 JUN 2011

Activity : 5th day - Network Test 3 : Tanjung Bidara

The third GPS observation location at Tanjung Bidara by using Topcon.

Setup the GPS instruments at the point behind the bus station.
Record the observation in 3 hours common data.

14 JUN 2011

Activity : 6th day - Network Test 4 : Tanjung Kling

The last GPS observation was made in Tanjung Kling, Jetty Tanjung Beruas by using
Magellan Z-Max.
Setup the GPS instruments at the monument at the jetty.

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 Record the observation in 3 hours common data.

15 JUN 2011

Activity : 7th day – Baseline Pillar Test

For our group, the observation was:

Venue: Ayer Keroh, Melaka in front MITC

Instrument: Magellan Z-Max 1

The observation was started at Pillar 1, and then moved to next pillar 2 until the last
observation at Pillar 5.
The raw data then was converted to RINEX files.
Using Leica SKI-Pro and GNSS Solution
Raining, placing the controller in the proper manner.

16 JUN 2011

Activity : 8th day - Data Processing and Recce Benchmark

At the day, 2 students from each group involve to do recce and find benchmark to do
heighting transfer and benchmark test in radius 20 km around Melaka.
Other student Stay in UiTM Bandaraya Melaka Tun Mutakhir College to process all of
those observed data.

17 JUN 2011

Activity : 9th day - Data Processing

Stay on UiTM Bandaraya Melaka Tun Mutakhir College to process all of those observed
data.
The data of network test, transfer CP and GPS calibration were being processed.

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18 JUN 2011

Activity : 10th day - Heighting Transfer And Benchmark Test.

The first observation test was made at Durian Tunggal near Kampung Gangsa Mosque
by using Topcon Hyper Ga.
The instrument was established on the benchmark No: M 0068
The second location observation test at Batu Berendam.
The instrument was established on the benchmark No: M 0390.
Observation was made 2 sessions with 1 hour per session of common data.
19 JUN 2011

Activity : 11th day - Data Processing

Processing the data.

Analysis the data.
Continue the report writing.

20 JUN 2011

Activity : 12th day - Report Writing and Processing

Processing the data.

Analysis the data.
Continue the report writing.

21 JUN 2011

Activity : 13th day - Report Submission and Viva

Submission the report and Viva session.

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1.8 EQUIPMENTS

1.8.1 Leica Sr500

No Part Of Instrument Function

1
Antenna will usually be mounted on a tripod or pillar.
The equipment will automatically begin to acquire and track
satellites and record data as set up in the Receiver configuration.

Antenna
2

The GPS Receiver is the instrument that processes the GPS signals
received by the GPS Antenna.

Receiver
3

Cable is used to make connection between Leica antenna and

receiver

Cable
4
System 500 powered by two GEB121 camcorder type batteries.
which plug into the underside
of the GPS receiver.

Two batteries, fully charged, will power the SR510 and TR500 for
about 7.5 hours continuously and the SR520/530 for about 6 hours
continuously.

Battery

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1.8.1.1component Of Receiver

Table List of equipment

No Component Of Receiver
1. Port 3. 8 pin Lemo.Power/data in/out
2. Event Input 1 (Optional)
3. 5 pin Lemo. Power
4. Power ON/OFF
5. PPS Output (Optional)
6. GPS Antenna in
7. Event Input 2 (Optional)
8. Port 2. 5 pin Lemo. Power/data in/out.
9. Pressure equalisation vent.
10. Port 1. 8 pin Lemo. Power/data in/out.
11. PC Card door.
12. Terminal in/out or Remote Interface in/out.

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1.8.2 Magellan Z-Max

No Component Function
1
The Receiver module contains the GNSS receiver, the
memory card, front panel display, external serial ports, USB
port, and power port.
The Receiver module also contains the internal Bluetooth®
module that allows the receiver to wirelessly communicate
with external devices.

Magellan Receiver Module

2
The Max-Trac GNSS antenna module contains the GNSS
antenna which allows the Z-Max.Net receiver to track
signals from the GPS satellites.

GNSS Antenna Module

3
The Power module contains rechargeable lithium ion
battery cells. The Power module has a capacity of 8.8 amp-
hours and should power the Z-Max.Net for over 13 hours in
typical user scenarios.

Power Module
4 All raw data recording in the Z-Max.Net is done on an SD
(Secure Digital) memory card. The SD memory card is a
highly-sophisticated memory device about the size of
SD receiver. The SD card is used to record data and load new
receiver firmware. The receiver comes with a 64 MB SD
card as standard, but SD cards with larger capacities are
Card available as options.
5
The HI measurement tool is used to provide a convenient
location on the Z-Max.Net system where the slant height of
the antenna above the mark can be consistently and
HI Measurement Tool accurately measured

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1.8.3Topcon Hiper Ga

No Component Function
1
The receiver contains the status LEDs for Data record (REC),
Battery (BAT), Receiver (Rx), and Start (STAT).It also contains
button to ON and RESET and Ports for power and USB. It also
contains internal Bluetooth module that allows the receiver to
wirelessly communicate with external device and memory for
storage data. It come with one set contain Base and Rover.
Receiver Module

2
Antenna used to track signals from GPS satellites. It consistently
track satellite above the horizon and provide good multipath
rejection for signals reflecting from surface such as the ground.

Antenna Module

3
The controller is used to interface with and control the base and
rover module. In practical used to setup configuration at base and
rover during static and kinematic survey.

Controller

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 CHAPTER 2

METHODOLOGY

2.0 INTRODUCTION

The procedure adopted in this project work forms the local coordinate using Topcon tools,
Leica Ski-Pro, GNSS and GDTS software. The stages involve in this project:

INSTRUMENT TEST

PLANNING AND
RECONAISSANCE

FIELD WORK

NETWORK TEST BASELINE TEST GPS HEIGHTING AND

BENCHMARK TEST

TRANSFER TRANSFER HEIGHT

CONTROL

DATA CONVERSION (RINEX)

DATA PROCESSING, ANALYSIS

AND REPORT

COORDINATE
TRANSFORMATION
16
2.1 INSTRUMENT TEST

2.1.1 Aim

This test is very important because it expose to students the way to handle and configure
Topcon, Leica and Magellan Z-Max properly. Other than that, it will also make students to
become familiar with those instruments and can handle and configure it properly.

2.1.2 Objective

 To make student able to use variety of GPS instrument such as Topcon, Leica and
Magellan Z- Max.

 To make sure the condition of instruments is better and can minimize problems during
the observation.

 To make students able to use, set up and configure the instruments by themselves before
starting job in site.

2.1.3 List and specifications of equipment

TYPES OF FREQUENCY CONDITION/REMARK

INSTRUMENT
Topcon 1 Dual OK
Topcon 2 Dual Only configure using
controller
Topcon 3 Dual OK
Leica 1 Dual Good condition but have
battery problem
Magellan Z-Max Dual OK
Magellan Z-Max Dual OK
Magellan Z-Max Dual OK

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2.1.4 Topcon Instrument Configuration

Procedure:

1. Firstly, set up the instrument on the tripod on the point mark or GPS monument.

Status Battery Status

Radio Link status

Record button Connect FC to Port Slant height

A of Base Receiver measure indicator

2. Then, the antenna height was measured from the point mark to the slant height indicator.
3. Reset button was selected to switch on the antenna.
4. FC connected controller was used to connect to Port A or Bluetooth.
5. After that, optional FC controller (TopSURV software) was used to configure antenna.
6. FN button was pressed to start recording.

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2.1.5 Magellan Z – Max Configuration

1. The first step is set up the instrument on the point mark.

2. Memory was reset from the setting menu

3. Next, the instrument was restart by pressing button on / off until it display re – initialize.

4. Wait for the instrument to get satellite’s signal. Job was created and survey motion was
selected.

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5. After that, in the job configuration the instrument height and elevation mask was set.
Then, the interval for collecting data was set.

6. Lastly, follow the instruction in the screen and press enter button to start sessions.

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2.2 PLANNING

Before we start our projects, our survey group make prepared a proper planning of what we are
going to do there. Preparations before us moving to survey work are such as software
configuration and equipments calibration.

2.3 RECONNAISSANCE

To get the overview of the GPS survey area at Tanjung Kling, Tebong, Lubuk China and Bukit
China for better planning before does measurement. The aim of the reconnaissance is to know
our location area or some problems will be coming when survey was started and also can get a
view about our site and became familiar with it. In this project, on the reconnaissance day our
job is to find existing monument located at state of Melaka. These monuments will be used
during the network test and transferring control points. We need four monument for this job.
First monument we get at and then STAPS Tanjung Kling (m 33), SMK Lubuk China ( GP 12),
SRJK(T) Tebong (GP 13), Bukit China (TG 03).

From the reconnaissance, we find 4 monuments to perform network test. After that, we did the
discussion on site schedule for all group and arrangement to all groups in 4 monuments. Firstly
we must to perform network test but the same time also perform transfer control point for point
Engine 1 and Engine 2 and to establish the local control point for Hydro 1, Hydro 2 used for part
5 student.

Monument Latitude Longitude Ellipsoid Height

Lubuk Cina 2ᵒ26” 53.64072’ 102ᵒ 04” 19.64397’ 16.937m

Tebong 2ᵒ26” 26.40545’ 102ᵒ 20” 23.12101’ 47.765m

Tanjung Kling 2ᵒ12” 53.9118’ 102ᵒ 09” 9.83020’ 3.713m

Bukit Cina 2ᵒ11” 54.73832’ 102ᵒ 15” 25.52985’ 46.722m

Table : list of Monument

21
2.4 NETWORK TEST

GPS monument test is performed in order to ensure that the operation of GPS receivers,
associated antennas and cabling, and data processing software, give high accuracy coordinate
results. The purpose of the GPS monument Test is to compare GPS observed coordinates with
their corresponding established GPS geodetic values.

The GPS network test site comprises of four (4) GPS stations (known stations). The test has
been carried out using GPS static technique. The observation has been carried out in one
session about 3 hours for common data using a total of eight GPS receiver.

2.4.1 Criteria of the network test that we performed:

 The test comprises about four different monument using static GPS.
 Four GPS monument at Tanjung Kling, Bukit China, Lubuk China, and Tebong
 The observation carried out in one session about three hour for common data using dual
frequency GPS receiver.

2.4.2 Condition of Network Test:

 All coordinates of the network test are known in local geodetic system.

 All stations have sky visibility of at least 90%.

 The test network should include a minimum of four (4) stations of the First Order GPS
Network of Peninsular (DSMM Report, 1994: “GPS Derived Coordinates”).

22
2.4.3 GPS Network Test

For our project, we used four (4) monuments which are located at Tanjung Kling, Lubuk
China, Batu China, and Tebong. For the observation, we need three hours for the observation
and it is crucial that all groups will have the common data where we will start and end the
observation on the same time.

LUBUK CINA

TEBONG

FOTO 1

TANJUNG KLING
ENG
1
BUKIT CINA
HYDRO 1

Establish Point Monument Point

2.4.4 Field Test Criteria

Observation length >3 hour

Recording Interval 1 second

Number of Satellites ≥4

GDOP ≤6

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 Sky Clearance ≥ 90%

Cut Off Angle 0°

2.4.5 Objectives

The objectives we conduct the network test are:

To compare GPS observed coordinates with their corresponding established GPS
geodetic values.

To test the instrument capability in terms of antenna, cabling and software.

To perform analysis and evaluate the results of data processing.

To analysis the baseline network for four (4) monuments.

2.4.6 JUPEM Guidelines

1. A network test should be performed to assure the operation of the GPS instrumentation
for the purpose of determining high accuracy relative coordinates.

2. The GPS instrumentation must be tested on part of the established high order geodetic
network (DSMM Report, 1994, “GPS Derived Coordinates”). The network should
include a minimum of three (3) existing First Order GPS Control stations as described in
the above DSMM report (1994).

3. The network test should be carried out on an annual basis, or when the receiver's
firmware or post-processing software is upgraded to a new version. In the later case, the
test should include the Zero Baseline Test and EDM Baseline Test.

24
4. The experimental setup of the network test as described in Appendix A.7 should be
followed.

5. The network test could be carried out over several GPS observation sessions. More than
one pair of GPS equipment could be used at the same time.

6. The test should be carried out on a station network with at least 90% sky visibility.

7. The network test should be carried out using the Static positioning method, with at least
two (2) hours observation sessions. All other recommended procedures should be
followed (as defined in these guidelines).

8. The receivers shall track at least five (5) satellites during the observation session with a
GDOP of less than six (6).

9. Cut-off angle of fifteen degrees (15°) should be applied during the baseline processing.

10. The minimally constrained network adjustment should be carried out using the computed
baselines expressed in the WGS84 datum.

11. The final coordinates should be given in the established local system. The recommended
coordinate transformation procedure should be followed.

12. The maximum allowable discrepancy between the surveyed coordinates (observed GPS
values) and the true coordinates (established values) for the network test must be less
than ten (10) millimeters in the horizontal component or relative accuracy of better than a
+ bL millimeters (a=5mm, b=2ppm, L= baseline length in kilometers), and less than
twenty (20) millimeters in the vertical component. If this tolerance is not met, the
surveyor will be required to validate the results by repeating the test again. If the test fails
again the datasets and results should be validated by the Geodetic Authority. If the results

25
 are still outside tolerance it is advised that the surveyor proceed to carry out zero baseline
and EDM baseline tests, or the equipment sent to the GPS agent for further testing.

2.4.7 Procedures

1. GPS network test has been carried out at the existing GPS geodetic network in Melaka
where the network site comprises of four GPS monuments. The monuments located on
different area which are Tanjung Kling, Lubuk Cina, Tebong, and Bukit Cina where the
distance between them is approximately 30 kilometers. The other four location for
establish point is at Tanjung Bidara for Fotography point, hydrography point at Pantai
Klebang, and for engineering point at Kolej Bandaraya Melaka (KBM), UITM.

2. The eight (8) instruments was fixed to each location and set up the instruments on the
monument station.

3. Before started the work, we have to set 1” for the sampling rate and 0° for the elevation
mask. The observation was done for three hours in order for all group to obtain common
data.

4. In order to achieve this, we have to wait for other group and start the observation on the
same time and also end on the same time.

5. All data obtain will be convert to RINEX for further data processing.

6. For the first day, we went to Bukit Cina and set the station name as BCNA. We used
Magellan Z-Max. The vertical height is 1.451 m.

7. On the next session, we make at UiTM Kampus Bandaraya Melaka and set the station
name as ENG 1. During this session, we used Leica and the vertical height is 1.375 m.

8. The third session, we went to Tanjung Bidara and set the station name as FOT 1. We
used Topcon and the vertical height is 1.205 m.

9. Later, we went to Tanjung Kling and set the station name as TKLG. We again using
Magellan Z – Max during this session and the vertical height are 1.517 m.
26
2.5 BASELINE PILLAR TEST

2.5.1 Aim

To ensure that the operation of a pair of GPS receivers, associated antennas and cabling, and
data processing software, which give distance results that can be compared with calibrated
baseline data. For this task, it was conducted h0 for at MITC Ayer Keroh, Melaka by using
three types of instrument which was Topcon, Leica and Magellan Z-Max. The test has been
carried out using GPS rapid static technique.

2.5.2 Objective
To check the precision and accuracy of the length given by those three types of GPS
instrument for the previous observation.

The value between pillars will use to compare with the value from the existing distance
from JUPEM value.

2.5.3 JUPEM Guidelines

1. An EDM baseline test should be performed to ensure the correct operation of a pair of
GPS receivers (and data processing software) that will be used for baseline measurement.

2. The GPS instrumentation shall be tested on an EDM baseline that itself has been
calibrated to a local standard of distance using a special a high quality EDM instrument.

3. The test shall be used to study the precision of the receiver measurements (and hence its
correct operation), as well as validate the data processing software.

4. EDM baseline test should be performed on a six monthly basis or prior to any large
survey campaign being carried out.

5. The test should be carried out at an established EDM baseline test site, by occupying
pillars with at least 90% sky visibility.

27
6. The experimental setup of the EDM baseline test as described in Appendix A.5 should be
followed.

7. The GPS receivers should be tested against the established EDM baseline lengths
(between pillars), varying from twenty (20) meters to about one (1) kilometer.

8. Each GPS receiver is to be connected to its designated antenna (mounted on the pillar)
using the same antenna cable used during surveys.

9. The test should be performed for a minimum of ten (10) minutes observation sessions.

10. The receivers shall track at least five (5) satellites during the test session with a GDOP of
less than six (6).

11. Cut-off angle of fifteen degrees (15°) should be applied during the baseline processing.

12. The resulting difference in slope distance between the GPS measurement and the
standard must be less than ten (10) millimeters. If this tolerance is not met the test should
be repeated, and if the equipment fails again the instrument should be returned to the GPS
agent for repair.

2.5.4 Purpose

To compare the length differences between observation values with true value from
JUPEM and to check whether the instruments are in the good condition or not for survey
work. The values should not exceed the accepted error limit fixed by JUPEM, within
10mm. The baseline test procedure as shown below.

The GPS test calibration site comprises of six (6) pillars separated at specified interval
with the longest baseline of about one (1) kilometer. The length between pillars has been
routinely measured and documented as the published true values.

The calibration has been carried out using GPS rapid static technique. The instrumental
setup given below has been followed throughout the calibrations.

28
 The baseline test procedure as shown below:

2.5.5 Procedure

1. In GPS baseline calibration, we have to calibrate all types of GPS instrument which
are Topcon, Leica and Z-Max.
2. For the first session, the GPS antenna was set up a Leica instrument at pillar 1,
Topcon 1 at pillar 2, Topcon 2 at pillar 3, Topcon 3 at pillar 4, Z – max at pillar 5.
The pillar 1,2,3,4 and 5 as a rover and the Z – max 2 at pillar 6 as a base. The
observation for 15 minutes each pillar.
3. Set the elevation mask 0ᵒand sampling rate 1”
4. Then, move the GPS antenna to second session set up a z – max 1 at pillar 1, Leica 1
at pillar 2, Topcon 1 at pillar 3, Topcon 2 at pillar 4, Topcon 3 pillar 5. The pillar
1,2,3,4 and 5 as a rover and the Z – max 2 at pillar 6 as a base. The observation for 15
minutes each pillar.
5. Repeat same step to move GPS antenna until all instrument finished observation.
6. After all observations on the pillars finished, all groups stop the observation
simultaneously.
7. The raw data then will convert to RINEX file and process. The result will compare
with the value from JUPEM.

PIL 1 PIL 2 PIL 3 PIL 4 PIL 5 PIL 6

Figure: Standard condition of Pillars calibration

29
 TIME OF PIL 1 PIL 2 PIL 3 PIL 4 PIL 5 PIL 6
OBSERVATION

1 LEICA 1 TOPCON 1 TOPCON 2 TOPCON 3 Z – MAX 3 Z – MAX 2

2 Z-MAX 1 LEICA 1 TOPCON 1 TOPCON 2 TOPCON 3 Z – MAX 2

3 Z- MAX 3 Z – MAX 1 LEICA 1 TOPCON 1 TOPCON 2 Z – MAX 2

4 TOPCON 3 Z – MAX 3 Z – MAX 1 LEICA 1 TOPCON 1 Z – MAX 2

5 TOPCON 2 TOPCON 3 Z – MAX 3 Z – MAX 1 LEICA 1 Z – MAX 2

6 TOPCON 1 TOPCON 2 TOPCON 3 Z-MAX 3 Z – MAX 1 Z – MAX 2

Table: Arrangement of the instrument for calibration baseline test

2.5.6 References Coordinates From JUPEM

No of Pillar Latitude Longitude Ellipsoid

1 2ᵒ 16’ 29.21357” 102ᵒ 17’ 11.94896” 19.736

2 2ᵒ 16’ 29.06065” 102ᵒ 17’ 11.31942” 19.224

3 2ᵒ 16’ 28.44814” 102ᵒ 17’ 08.80298” 17.602

4 2ᵒ 16’ 27.68632” 102ᵒ 17’ 05.65598” 16.366

5 2ᵒ 16’ 26.76946” 102ᵒ 17’ 01.88083” 15.397

6 2ᵒ 16’ 25.39493” 102ᵒ 16’ 56.21760” 13.667

30
2.6 TRANSFER CONTROL POINTS (GPS MONUMENT)

2.6.1 Aim

Transfer of controls includes making static observations using dual frequency GPS receivers.
Transfer control point acquires at least 4 control points as a base. This task was done for 2
points of Hydrographic, 2 points of Engineering and 2 points of Photogrammetric base on
reference base from the network test.

2.6.2 Objective

To get the coordinate for control point.

The coordinate then will transform from WGS84 to Cassini for specific point
(Engineering, Photogrammetric)

2.6.3. Procedures

Session 1, 2 and 3
1. The GPS instrument is setup on the Engineering 1, Engineering 2, Photogrammetric 1,
and Photogrammetric 2.
2. The reference bases for those points are from Tebong, Lubuk Cina, Bukit Cina and
Tanjung Kling.
3. All the observations take about 3 hours and simultaneously.
4. The raw data then will convert to RINEX file and process base on 4 reference base
(Tebong, Lubuk Cina, Bukit Cina and Tanjung Kling.)
5. The coordinate from the final process will then transform to a specific local
coordinate.

Session 4
1. The GPS instrument is setup on the Hydrographic 1 , Hydrographic 2, Engineering 2,
and Engineering 3.
2. The reference bases for those points are from Tebong, Lubuk Cina, Bukit Cina and
Tanjung Kling.

31
 3. All the observations take about 3 hours and simultaneously.
4. The raw data then will convert to RINEX file and process base on 4 reference base
(Tebong, Lubuk Cina, Bukit Cina and Tanjung Kling)
5. The coordinate from the final process will then transform to a specific local
coordinate

2.7 COORDINATE TRANSFORMATION TO LOCAL COORDINATE SYSTEM

The minimally constrained network adjustment should be carried out using the computed
baselines expressed in the WGS84 datum. The coordinate for control point will transform
to local coordinate system for specific use.

The coordinate transformation was done for:

 Engineering ( ENG1 & ENG2)

 Hydrographs (HYD1 & HYD2)

 Photogrammetric ( FOT1 & FOT2)

All the transformation process will do in transformation software ( DGTS). Below is flow
of transformation coordinate to local system :

WGS 84 / PMSGN 94

MRT 48

MRSO

CASSINI SOLDNER (OLD)

32
2.7.1 Coordinates Transformation Procedures

1. The resulting GPS coordinates are in a geocentric datum such as WGS84, and need to be
transformed into the established local coordinate system. The existing coordinate system
used for cadastral survey in Peninsular Malaysia is the local Cassini Soldner System.
2. The transformation process comprises the following steps:
Coordinate transformation from WGS84 to local Malayan Revised Triangulation
System (MRT48).
Coordinate transformation from local MRT48 system to the existing local
Rectified Skew Orthomorphic Projection System (MRSO).
Coordinate transformation from MRSO system to the local Cassini Soldner
System (Cassini).
3. Transformation from WGS84 to MRT should be carried out as follows:
The Bursa-Wolf mathematical model should be used.
The local MRT system should be referenced to the Modified Everest ellipsoid.
The official seven (7) transformation parameters should be used. Three (3) are
the translations parameters, another three (3) are the rotation parameters, and one
(1) is the scale factor.
The standard algorithm that has been developed for the purpose should be used
for the transformation.
4. Transformation from MRT48 to MRSO should be carried out as follows:
The mathematical model that should be used is based on the formula published in
the Projection Tables for Malaya.
The RSO is also based on the Modified Everest reference ellipsoid.
The origin for the MRSO projection system is based on the geographical
coordinates of Kertau.
5. Transformation from MRSO to Cassini should be carried out as follows:

33
1. Open software GDTS Version 4.1

2. The Geodetic Datum Transformation System 4.1 will be appear, then, click button continue

WGS84 TO MRT48

3. Select Peninsular Malaysia and then select 3Dimensional Transformation. On transformation

module select PMSGN 94 to MRT 48. Enter the coordinate of station (for example TKLG).
And then click button Transform

34
4. After transformation, click button save as to save this file in format.txt

MRT48 TO MRSO

5. Click at the map projection as Sub-Modules and choose MRT48 to MRSO

35
6. Key in the coordinate (latitude, longitude, and) from MRT coordinates. And then click button
transform.

7. Click button “preview and print” to save the coordinate

36
8. MRSO TO CASSINE

9. On the map projection, choose MRSO to Cassini – Soldner (Old) and select name of state
(Melaka)

10. Enter the value MRSO from previous transform. And then click transform button and save
the coordinate

37
2.8 GPS HEIGHTING

2.8.1 Aim
This GPS height was done for 6 benchmarks from 2 references base in order to check the
ellipsoid height give by GPS instrument.

2.8.2 Objective
To check the accuracy of the ellipsoid height.
Transfer the ellipsoid height to orthometric height.
The first and second hour value will compare with the value from JUPEM in order to
calculate the difference value between JUPEM and observation.
2.8.3 Procedures
1. All the six of benchmarks are located along the route of Jalan Bachang to Jalan
Durian Tunggal.
2. Reconnaissance was done to choose 6 benchmarks which located nearly among
together for BM testing.
3. Choose monument at Tebong and point at ENG1 as Base points. Use Z-max and leica
equipments because both it can observed more than 4 hours nonstop.
4. Set all the 6 of BM as rovers.
5. On the observation day, 2 reference bases were used for 2 hours observation. Divided
by two session of one hour observation.
6. All GPS instrument use at each location of one to six benchmarks.
7. Topcon (BM1), Z-Max (BM2), Topcon (BM3), Leica (BM4), Z-Max (BM5) and for
last benchmark use Z-Max (BM6) would observed for the first hour simultaneously to
get the common time observation.
8. Two point at ENG 1 and TBNG already static at their location and was observed by
two hour of observation nonstop. So please make sure that the batteries of that
instrument used was in fully charged.
9. Then, all the GPS instruments will change the location of benchmark for the second
one hour observation. Z –Max (BM1), Topcon (BM2) and Leica (BM3), Topcon
(BM4) and Z-Max (BM5), Z-Max (BM6).
38
 10. After finished the observation, transfer all the raw data into computer systems and all
the raw data should be converted to the RINEX file and then be processed in Leica
Ski Pro software.
11. All the GPS observation that was convert into orthometric height would be compared
with the height of BM value from JUPEM.

2.8.4 Processing

There are two method of processing in BM heighting. One which is data from two base
will transfer to the point 1 as BM1. Next by using the same base points transfer to the
second point as BM2. Process until 5 points.

The value is in ellipsoid height then it should be converted into orthometric height before
it value can be used to compared with the value of JUPEM heighting. The difference
between observed values with the given value by JUPEM must be in the range of
allowable difference values.

As a proving method, the total of minus values from observed value of BM 2 and BM 3
should be equal with the total of minus values of BM 2 and BM 3 that given from JUPEM.
The difference values should be in the 0.1m of tolerances values.

For the second method, used the heighting on the point 1 that already get from method one
as a base point. This base point will replaced the previous base points. Then from this new
base point, process the data to transfer the heighting on the another 4 points of BM. The
heighting will be process on the ellipsoid height then that value should be convert into
orthometric height to compared with the heighting of BM that was calculated on method
one before..

39
 figure: (left) Bench mark at Kampung Gangsa,Durian Tunggal Melaka

(right) Bench mark at main road to Durian Tungga

Process 1
Process 1

ENG 3 TBNG BASE

BM 1
BM 1
BASE

BM 2
BM 2

COMPARE
BM 3
BM 3

BM 4

BM 4

BM 5

BM 5

BM 6

40
BM 6
2.8.5 Benchmark True Height

No of BM Venue True Height

BM 1 M0804 DEWAN PERSATUAN DEWA KUANYIN 3.44M

BM2 M0142 OPPOSITE PETRONAS BATU BERENDAM 7.017M

BM3 M0068 DEWAN BALAIRAYA KG. GANGSA 10.298

BM4 M0390 JALAN DURIAN TUNGGAL NEAR MARDEC 11.66

FACTORY

BM5 M0109 MARDEC FACTORY 13.027

BM6 M0807 SEK. MEN.KEB DURIAN TUNGGAL 15.333

Table: location of Benchmark

2.8.5 Orthometric Height

The Orthometric height is the distance H along a line of force from a given point P at the
physical surface of an object to the geoid.

H=h–N

Orthometric Height = Ellipsoid Height – Geoid Height

Figure : Orthometric Height

41
 CHAPTER 3

DATA PROCESSING

3.0 INTRODUCTION

Processing data would involved for result and analysis using Leica SKI-Pro, Topcon
Tools, GNSS Solutions amd GDTS.

P R O C E S S I N G

DATA CONVERSION
(RINEX)

DATA PROCESSING

GDTS

COORDINATE
TRANSFORMATION

42
3.1 DATA CONVERSION IN RINEX DATA

3.1.1 GNSS PROCESS STEPS

1. Firstly, run the GNSS solution software by clicking on the GNSS Solution button.

2. Choose Create a new project to process intended data. Other than that, you can also
choose to Open an existing project, Open the last project you worked on or Run
without a project.

43
3. Next, enter your Project Name and click OK.

4. To import data, choose Import Raw Data from Files from the various selection of
importing the data.

44
5. Select the intended rinex raw data to be opened.

6. After finished the importing process, choose the Base or Control Point for the
network process.

45
7. You need to edit the Latitude, Longitude and Heighting value as given by the Jupem

8. Rename “project name” as new name refer to the project name. Then click “ok”.

46
9. Then click “Import Raw Data from files” to import “RINEX data”

10. Browse “rinex data” from your database. Select all data if you want to process all data
in one processing. But if you want to process by using different observation your can
select the needed rinex data only.

11. Change files of type into “RINEX RAW DATA FILE” then click “open” button.

47
12. The importing of rinex file will appear on “importing GPS Data”. Check the list of
data to makesure all the data is already importing. Select list of data that you want to
use. Next is click on button “OK” then select “to import”.

13. The results will show in window below.

48
14. Next is to repairing the data. Check all the info such as site, antenna height, antenna
type, height type. The antenna height should be follow the measurement on site,
antenna type follow the type of equipment uses, and height type must set in “vertical”

49
15. To edit the data highlight the data and then right click to open properties. Click on file
and change the “antenna type” into the true antenna. Leica = LEIAT 502; Topcon =
TPS hypier GA/BA; Magelland = Z=max.

16. Next click on occupations, check the antenna height and antenna type into vertical.
Then click “Apply to all” button. Then click OK.

50
17. After all the data was is corrected, you can start the processing job. Firstly click on
adjustment tools. Then select “define Control Point” as a base to the all points.

18. Next click on “process option”

19. Highlight all the data then click on OK button then select on “to save and process
selected baselines”. The processing of baseline will be begun.

51
20. After finish the processing, click on “export button” and select “land survey report.

52
3.1.2 LEICA SKI – PRO 3.0

1. Firstly, run the SKI - Pro software by clicking on the SKI – Pro icon. Ski-Pro
window will appear and just click Close.

2. Go to File, choose New Project.

53
3. Then you need to create a new project and give your project name such as
“day1_lcna”. If you’re already having old project, just click the Open Existing
Project button.

OR

Open Existing

4. Set the Project Name while the other settings as default setting then click OK.

54
5. Then the New Project window will be displayed.

6. The first steps before you start processing is to have the data to be processed. Go to
Import function and choose the Raw Data function.

55
7. Choose the intended raw data to be opened. For example, we would like to do the
network test, so we need to import the rinex file (*.11o) to be processed. After
choosing the raw data, click Import.

8. Then, choose the intended project to be assigned. Then click on the Assign button.

56
9. Your project will look like this.

10. Click on the Select Mode : Reference button and then click on the intended Base or
Reference point. The selected point will be highlighted in red colour.

57
11. Do the same steps to choose the Rover point. The Rover points will be highlighted in
green colour.

12. Then click on the Data Processing Parameters.

13. Then, it appears the GPS Configuration Processing Parameters. At the General
tab, we need to set the Elevation Mask (00°) and check on the Show advanced
parameters.

58
14. Next, on the Strategy tab, select the Sampling Rate for 1 second. After finished all
the configurations, click OK.

15. Then, go to the Points tab at the bottom, and choose the Base point. Right click at the
Base point, choose the Properties.

59
16. Next, at the Point Properties window, select Point Class as Control and filled in the
true value of Latitude, Longitude and Height of the Control or Base point. Then,
when finished setting, click Apply and OK.

17. After that, again, go to GPS Proc tab, start Process the network among the points.

60
18. After finished, go to Results you can see the results of each Rover points. Save the
report.

61
3.1.3 TOPCON TOOLS

All processing GPS Data used Topcon Tools software. The steps are explain below:

1. Open Topcon Tools software.

2. The Topcon Tools window will appear. For the new project click New Job at
the startup window to create a New Job.

3. Insert the project name. Click OK

4. Click at the Edit Configuration to setup

Time, Coordinate Systems, Unit and Other
relate to the process and then click OK.

62
 4. Time should be select GMT+8.00
times depend on the location.

5. Click at the Job then select the Import to import raw data from files

6. Import Raw data

 Import the data from file directory.

 First, import the master data
 Please check the data time based on your observation time
 Bellow show the example of raw data

Raw data

63
  Select the Antenna Type
 Insert the Antenna Height
Rename the  Choose the Antenna Height
Raw data Method

Observation times

7.This figure show the observation timeline for the every GPS points

64
8. Click at the GPS point to edit the timeline. Select the data that not complete. Then right click.
Select Disable. Then OK. Repeat this step for all the GPS points.
Click

Disable

9. After complete all above steps. For the processing Click at the Process to select the
GPS+Processing and then Adjustment.

65
 This figure show the GPS data point after processing. The green line means that the data
is in good condition. If red line appear showed that the data contain some error.

This figure show the GPS data point after processing. The green line means that
the data is in good condition. If red line appear showed that the data contain some
error.

66
 CHAPTER 4

RESULT AND ANALYSIS

4.0 NETWORK TEST

The result for elevation mask of 0º for all the four days, we find that the reading for GPS
monument at Bukit China is out of place because it is not a GPS monument instead it is a CRM
monument which used for cadastral work. Hence the reading of the output is not reliable and the
value of cause differ from what coordinate value from JUPEM.

average 0* GNSS

BCNA 102 15 26 2 11 55.22 17.003

LCNA 102 4 19.64 2 26 53.64 3.2525
TBNG 102 20 23.1 2 26 26.4 46.101
TKLG 102 9 9.83 2 12 53.96 48.061

AVERAGE 0* ski pro

BCNA 2 11 55.26 102 15 26.1 45.8924

LCNA 2 26 53.64 102 04 19.64 16.9138
TKLG 2 12 53.96 102 09 9.83 3.6646
TBNG 2 26 26.41 102 20 23.1 47.8321

NEWEST OF TPCN
AVRGE 0*

BCNA 2 11 55.22 102 14 2.82

LCNA 2 26 53.6 102 4 19.64

67
 TBNG 2 26 26.41 102 20 23.1
TKLG 2 12 53.96 102 9 9.83

JUPEM value:

BCNA 102° 15' 2° 11' 54.73832"N 46.722

25.52985"E
LCNA 102° 04' 2° 26' 53.64072"N 16.937
19.64397"E
TBNG 102° 20' 2° 26' 26.40545"N 47.765
23.12101"E
TKLG 102° 09' 2° 12' 53.96118"N 3.713
09.83020"E

From these 4 GPS monument, Bukit China (BCNA) give a high error and it is out of the
tolerance, thus for the next calculation and reference onwards we do not count BCNA as one of
our control because it is consider as out of position.

Based on this result we can say that the reading of coordinates after we set Bukit China (BCNA)
as control are different from other control which is Lubuk China, Tebong and Tanjung Keling.
Hence we only calculate the average from reference from these 3 controls only.

Different can also be detected when using different value of elevation mask.

68
APPLICATION SOFTWARE : LEICA SKI - PRO 3.0

ELEVATION MASK : 0⁰ and 10⁰

SAMPLING RATE : 1 Sec
FREQUENCY : AUTOMATIC
BASE : TANJUNG KLING (TKLG)

Elevation mask 0⁰
ELEVATION
LONGITUDE (E) LATITUDE (N)
(m)
2º 11' 55.34238"
BCNA 102º 15' 26.27996" E N 46.0342
2º 26' 53.64049"
LCNA 102º 04' 19.64442" E N 16.997
2º 26' 26.40446"
TBNG 102º 20' 23.12140" E N 47.8161

Elevation mask 10⁰

ELEVATION
LONGITUDE (E) LATITUDE (N)
(m)
BCNA 102° 15' 26.28000" E 2° 11' 55.34240" N 46.035m
LCNA 102° 04' 19.64466" E 2° 26' 53.64085" N 17.0211 m
TBNG 102° 20' 23.12142" E 2° 12' 26.40443" N 47.8156m

The different

DIFFERENCE IN m DIFF IN cm
LONG ELEVATION LONG LAT ELEVATION
LAT (N)
(E) (m) (E) (N) (cm)
BCNA -0.0012 -0.0006 -0.0008 -0.12 -0.06 -0.08
LCNA -0.0072 -0.0108 -0.0241 -0.72 -1.08 -2.41
TBNG -0.0006 0.0009 0.0003 -0.06 0.09 0.03

69
APPLICATION SOFTWARE : LEICA SKI - PRO 3.0

ELEVATION MASK : 0⁰ and 15⁰

SAMPLING RATE : 1 Sec
FREQUENCY : AUTOMATIC
BASE : TANJUNG KLING (TKLG)

Elevation mask 0⁰
ELEVATION
LONGITUDE (E) LATITUDE (N)
(m)
102º 15' 26.27996" 2º 11' 55.34238"
BCNA E N 46.0342
102º 04' 19.64442" 2º 26' 53.64049"
LCNA E N 16.997
102º 20' 23.12140" 2º 26' 26.40446"
TBNG E N 47.8161

Elevation mask 15⁰

ELEVATION
LONGITUDE (E) LATITUDE (N)
(m)
BCNA 102° 15' 26.28002" E 2° 11' 55.34235" N 46.0341 m
LCNA 102° 04' 19.64436" E 2° 26' 53.64044" N 16.9900 m
TBNG 102° 20' 23.12141" E 2° 26' 26.40444" N 47.8158 m

The different

DIFFERENCE IN m DIFF IN cm
LONG LAT ELEVATION LONG LAT ELEVATION
(E) (N) (m) (E) (N) (cm)
BCNA -0.0018 0.0009 0.0001 -0.1800 0.0900 0.0100
LCNA 0.0018 0.0015 0.007 0.1800 0.1500 0.7000
TBNG -0.0003 0.0006 0.0003 -0.0300 0.0600 0.0300

70
APPLICATION SOFTWARE : TOPCON TOOLS

ELEVATION MASK : 0⁰ and 10⁰

SAMPLING RATE : 1 Sec
FREQUENCY : AUTOMATIC
BASE : TANJUNG KLING (TKLG)

Elevation mask 0⁰
ELEVATION
LONGITUDE (E) LATITUDE (N)
(m)
BCNA 102°15'26.28005E 2°11'55.34232N 46.011
LCNA 102°04'19.64397E 2°26'53.63960N 17.014
TBNG 102°20'23.11993E 2°26'26.40388N 47.82

Elevation mask 10⁰

ELEVATION
LONGITUDE (E) LATITUDE (N)
(m)
BCNA 102°15'26.28015E 2°11'55.34225N 46.013
LCNA 102°04'19.64427E 2°26'53.63956N 17.043
TBNG 102°20'23.11985E 2°26'26.40388N 47.83

The different

DIFFERENCE IN m DIFF IN cm
ELEVATION
LONG (E) LAT (N) ELEVATION (m) LONG (E) LAT (N)
(cm)
BCNA -0.003 0.0021 -0.0020 -0.3000 0.2100 -0.2000
LCNA -0.0066 0.0012 -0.0290 -0.6600 0.1200 -2.9000
TBNG 0.0024 0.0000 -0.0100 0.2400 0.0000 -1.0000

71
APPLICATION SOFTWARE : TOPCON TOOLS

ELEVATION MASK : 0⁰ and 15⁰

SAMPLING RATE : 1 Sec
FREQUENCY : AUTOMATIC
BASE : TANJUNG KLING (TKLG)

Elevation mask 0⁰
ELEVATION
LONGITUDE (E) LATITUDE (N)
(m)
BCNA 102°15'26.28005E 2°11'55.34232N 46.011
LCNA 102°04'19.64397E 2°26'53.63960N 17.014
TBNG 102°20'23.11993E 2°26'26.40388N 47.82

Elevation mask 15⁰

ELEVATION
LONGITUDE (E) LATITUDE (N)
(m)
BCNA 102°15'26.28042E 2°11'55.34241N 46.005
LCNA 102°04'19.64419E 2°26'53.63996N 17.009
TBNG 102°20'23.12046E 2°26'26.40410N 47.823

The different

DIFFERENCE IN m DIFF IN cm
LONG ELEVATION LONG LAT ELEVATION
LAT (N)
(E) (m) (E) (N) (cm)
BCNA -0.0111 -0.0027 0.006 -1.11 -0.27 0.6
LCNA -0.0066 -0.0108 0.005 -0.66 -1.08 0.5
TBNG -0.0159 -0.0066 -0.003 -1.59 -0.66 -0.3

72
APPLICATION SOFTWARE : GNSS SOLUTIONS

ELEVATION MASK : 0⁰ and 10⁰

SAMPLING RATE : 1 Sec
FREQUENCY : AUTOMATIC
BASE : TANJUNG KLING (TKLG)

Elevation mask 0⁰
ELEVATION
LONGITUDE (E) LATITUDE (N)
(m)
BCNA 102° 15' 26.28031"E 2° 11' 55.34240"N 46.015
LCNA 102° 04' 19.64430"E 2° 26' 53.64039"N 16.978
TBNG 102° 20' 23.12095"E 2° 26' 26.40514"N 47.775

Elevation mask 10⁰

ELEVATION
LONGITUDE (E) LATITUDE (N)
(m)
BCNA 102° 15' 26.28034"E 2° 11' 55.34238"N 46.02
LCNA 102° 04' 19.64441"E 2° 26' 53.64037"N 16.987
TBNG 102° 20' 23.12082"E 2° 26' 26.40510"N 47.767

The different

DIFFERENCE IN m DIFF IN cm
ELEVATION
LONG (E) LAT (N) ELEVATION (m) LONG (E) LAT (N)
(cm)
BCNA -0.0063 -0.0105 -0.0050 -0.6300 -1.0500 -0.5000
LCNA -0.0033 0.0006 -0.0090 -0.3300 0.0600 -0.9000
TBNG 0.0039 0.0012 0.0080 0.3900 0.0120 0.8000

73
APPLICATION SOFTWARE : GNSS SOLUTIONS

ELEVATION MASK : 0⁰ and 15⁰

SAMPLING RATE : 1 Sec
FREQUENCY : AUTOMATIC
BASE : TANJUNG KLING (TKLG)

Elevation mask 0⁰
ELEVATION
LONGITUDE (E) LATITUDE (N)
(m)
BCNA 102° 15' 26.28031"E 2° 11' 55.34240"N 46.015
LCNA 102° 04' 19.64430"E 2° 26' 53.64039"N 16.978
TBNG 102° 20' 23.12095"E 2° 26' 26.40514"N 47.775

Elevation mask 15⁰

ELEVATION
LONGITUDE (E) LATITUDE (N)
(m)
BCNA 102° 15' 26.28055"E 2° 11' 55.34275"N 46.021
LCNA 102° 04' 19.64457"E 2° 26' 53.64070"N 16.977
TBNG 102° 20' 23.12101"E 2° 26' 26.40545"N 47.765

The different
DIFFERENCE IN m DIFF IN cm
LONG LAT ELEVATION LONG ELEVATION
LAT(N)
(E) (N) (m) (E) (cm)
BCN
-0.0072 -0.0105 -0.1800 -0.7200 -1.0500 -1.8000
A
LCNA -0.0081 -0.0093 0.0010 -0.8100 -0.9300 0.1000
TBNG -0.0018 -0.0093 0.0100 -0.1800 -0.9300 1.0000

From these results, we figure that the error occurred in the coordinate are bigger with bigger
value of elevation mask. This can be said occurred from the obtuse angle of the satellite signal
received. The more obtuse the angle of satellite the higher probability for the GPS to received
inaccurate data. as the travel time will take much longer time than an acute angle. Hence it gone
through more obstacle along the way and resulted to inaccurate readings.

74
4.1 BASELINE TEST

Cut of angle = 00°

E. Diff E Diff N
pillar 1 LONG (E) LAT (N) height (cm) (cm) Diff H
JUPEM 102° 17' 11.94896" 2° 16' 29.21357" 19.737
L1P1 102° 17' 11.94867" 2° 16' 29.21317" 19.729 0.9667 1.3333 0.008
T1P1 102° 17' 11.94940" 2° 16' 29.21342" 19.7861 1.4667 0.5 -0.0491
T2P1 102° 17' 11.94983" 2° 16' 29.21331" 19.825 2.9 0.8667 -0.088
T3P1 102° 17' 11.94940" 2° 16' 29.21355" 19.7943 1.4667 0.0667 -0.0573
Z1P1 102° 17' 11.94905" 2° 16' 29.21367" 19.7421 0.3 0.3333 -0.0051
Z2P1 102° 17' 11.94938" 2° 16' 29.21366" 19.7502 0.2904 0.3 -0.0132

E.
pillar 2 LONG (E) LAT (N) height Diff E Diff N Diff H
JUPEM 102° 17' 11.31942" 2° 16' 29.06065" 19.224
L1P2 102° 17' 11.31947" 2° 16' 29.06055" 19.2178 0.1667 0.3333 0.0062
T1P2 102° 17' 11.31897" 2° 16' 29.06033" 19.2569 1.5 1.0667 -0.0329
T2P2 102° 17' 11.31961" 2° 16' 29.06050" 19.2668 0.6 0.5 -0.0428
T3P2 102° 17' 11.31968" 2° 16' 29.06077" 19.282 0.8667 0.4 -0.058
Z1P2 102° 17' 11.31942" 2° 16' 29.06064" 19.2373 0 0.0333 -0.0133
Z2P2 102° 17' 11.31952" 2° 16' 29.06080" 19.2246 0.3333 0.5 -0.0006

E.
pillar 3 LONG (E) LAT (N) height Diff E Diff N Diff H
JUPEM 102° 17' 08.80298" 2° 16' 28.44814" 17.602
L1P3 102° 17' 08.80350" 2° 16' 28.44813" 17.609 1.7333 0.0333 -0.007
T1P3 102° 17' 08.80324" 2° 16' 28.44816" 17.6351 0.8667 0.0667 -0.0331

75
T2P3 102° 17' 08.80280" 2° 16' 28.44777" 17.6369 0.6 1.2333 -0.0349
T3P3 102° 17' 08.80327" 2° 16' 28.44807" 17.6298 0.9666 0.2333 -0.0278
Z1P3 102° 17' 08.80347" 2° 16' 28.44795" 17.609 1.6333 0.0667 -0.007
Z2P3 102° 17' 08.80339" 2° 16' 28.44815" 17.6192 1.3667 0.0333 -0.0172

E.
pillar 4 LONG (E) LAT (N) height Diff E Diff N Diff H
JUPEM 102° 17' 05.65598" 2° 16' 27.68632" 16.366
L1P4 102° 17' 05.65624" 2° 16' 27.68650" 16.3608 0.8667 0.6 0.0052
T1P4 102° 17' 05.65641" 2° 16' 27.68654" 16.4057 1.4333 0.7333 -0.0397
T2P4 102° 17' 05.65631" 2° 16' 27.68659" 16.3967 1.1 0.9 -0.0307
T3P4 102° 17' 05.65591" 2° 16' 27.68624" 16.3954 0.2333 0.2666 -0.0294
Z1P4 102° 17' 05.65648" 2° 16' 27.68642" 16.3393 1.6667 0.3333 0.0267
Z2P4 102° 17' 05.65609" 2° 16' 27.68635" 16.3359 0.3667 0.1 0.0301

E.
pillar 5 LONG (E) LAT (N) height Diff E Diff N Diff H
JUPEM 102° 17' 01.88083" 2° 16' 26.76946" 15.397
L1P5 102° 17' 01.88134" 2° 16' 26.76945" 15.0451 1.7 0.0333 0.3519
T1P5 102° 17' 01.88104" 2° 16' 26.76975" 15.4628 0.7 0.9667 -0.0658
T2P5 102° 17' 01.88111" 2° 16' 26.76957" 15.446 0.9333 0.3667 -0.049
T3P5 102° 17' 01.88103" 2° 16' 26.76959" 15.4442 0.6667 0.4333 -0.0472
Z1P5 102° 17' 01.88119" 2° 16' 26.76952" 15.3888 1.2 0.2 0.0082
Z2P5 102° 17' 01.88077" 2° 16' 26.76950" 15.4002 0.2 0.1333 -0.0032

76
Cut of angle = 15°

E. Diff E Diff N
pillar 1 LONG (E) LAT (N) height (cm) (cm) Diff H
JUPEM 102° 17' 11.94896" 2° 16' 29.21357" 19.737
L1P1 102° 17' 11.94866" 2° 16' 29.21322" 19.7268 1 1.1667 0.0102
T1P1 102° 17' 11.94947" 2° 16' 29.21342" 19.7907 1.7 0.5 -0.0537
T2P1 102° 17' 11.95028" 2° 16' 29.21319" 19.8537 4.4 1.26 -0.1167
T3P1 102° 17' 11.94941" 2° 16' 29.21355" 19.7954 1.5 0.0667 -0.0584
Z1P1 102° 17' 11.94904" 2° 16' 29.21368" 19.7434 0.2667 0.3667 -0.0064
Z2P1 102° 17' 11.94938" 2° 16' 29.21368" 19.7545 1.4 0.3667 -0.0175

E.
pillar 2 LONG (E) LAT (N) height Diff E Diff N Diff H
JUPEM 102° 17' 11.31942" 2° 16' 29.06065" 19.224
L1P2 102° 17' 11.31944" 2° 16' 29.06055" 19.2183 0.0667 0.333 0.0257
T1P2 102° 17' 11.31897" 2° 16' 29.06033" 19.2571 1.5 1.0667 0.0131
T2P2 102° 17' 11.31964" 2° 16' 29.06050" 19.2693 0.733 0.5 0.0253
T3P2 102° 17' 11.31954" 2° 16' 29.06080" 19.2738 0.4 0.5 0.0298
Z1P2 102° 17' 11.31940" 2° 16' 29.06066" 19.2422 0.667 0.333 0.0182
Z2P2 102° 17' 11.31952" 2° 16' 29.06080" 19.2244 0.333 0.5 0.0004

E.
pillar 3 LONG (E) LAT (N) height Diff E Diff N Diff H
JUPEM 102° 17' 08.80298" 2° 16' 28.44814" 17.602
L1P3 102° 17' 08.80351" 2° 16' 28.44814" 17.6137 1.7667 0 0.0117
T1P3 102° 17' 08.80322" 2° 16' 28.44817" 17.6369 0.8 0.1 0.0349
T2P3 102° 17' 08.80278" 2° 16' 28.44776" 17.6361 0.666 1.266 0.0341
T3P3 102° 17' 08.80321" 2° 16' 28.44809" 17.6263 0.766 0.166 0.0243

77
 Z1P3 102° 17' 08.80350" 2° 16' 28.44794" 17.6101 1.7333 0.6667 -0.0081
Z2P3 102° 17' 08.80352" 2° 16' 28.44812" 17.6269 1.8 0.066 0.0249

E.
pillar 4 LONG (E) LAT (N) height Diff E Diff N Diff H
JUPEM 102° 17' 05.65598" 2° 16' 27.68632" 16.366
L1P4 102° 17' 05.65626" 2° 16' 27.68648" 16.3592 0.936 0.53328 -0.0068
T1P4 102° 17' 05.65639" 2° 16' 27.68655" 16.4069 1.368 0.76668 0.0409
T2P4 102° 17' 05.65628" 2° 16' 27.68659" 16.3982 0.996 0.9 0.0322
T3P4 102° 17' 05.65599" 2° 16' 27.68640" 16.3983 0 0.26664 0.0323
Z1P4 102° 17' 05.65655" 2° 16' 27.68641" 16.3434 1.896 0.3 -0.0226
Z2P4 102° 17' 05.65595" 2° 16' 27.68636" 16.3268 0 0.13332 -0.0392

E.
pillar 5 LONG (E) LAT (N) height Diff E Diff N Diff H
JUPEM 102° 17' 01.88083" 2° 16' 26.76946" 15.397
L1P5 102° 17' 01.88142" 2° 16' 26.76943" 15.0497 1.968 -0.10008 -0.3473
T1P5 102° 17' 01.88106" 2° 16' 26.76975" 15.4636 0.768 0.9666 0.0666
T2P5 102° 17' 01.88109" 2° 16' 26.76958" 15.4497 0.864 0.39996 0.0527
T3P5 102° 17' 01.88101" 2° 16' 26.76959" 15.4463 0.6 0.43332 0.0493
Z1P5 102° 17' 01.88099" 2° 16' 26.76954" 15.3754 0.54 0.26664 -0.0216
Z2P5 102° 17' 01.88069" 2° 16' 26.76947" 15.3974 -0.468 0.03324 0.0004

Analysis

1) Topcon3 shows that it can give a much accurate readings when the elevation mask is 15º
rather than 0º. This can be said as a result of in 15º elevation mask consists of a more
accurate signal that produce a much better data.

78
2) Z-max2 also agrees with the theory. It gives readings of 0 and 15 in the same manner as
Topcon 3.
3) However, the four other GPS instruments does not agree with these statements. The
readings are inconsistent.
4) This can be said due to the multipath error that might occur during the observation. This
is because there are many buildings near the observation site thus affected the readings of
the output.
5) This observation also shows that between 0 and 15 degree angle, there exist just a little
different in the readings recorded. The error in within the acceptable tolerance.
6) We can also conclude that the much more visible satellite connected, the higher the
precision.
7) Large amount of satellites give accurate output particularly in height measurement.
8) The angle of satellite is also taken into account as 0d measurement can detect many
satellite rather than 15d.
9) 0d elevation mask can detect more satellites but at the same time but can transmit longer
signal hence create more error.
10) Satellites which are low in horizon from the observing position will have more errors
included in their observation. 15d elevation mask is set to eliminate low elevation
satellite.
11) Better observation value also depends on the specification stated by JUPEM. JUPEM
uses 10d as elevation mask, hence, the result for greater than 10d uses in GPS
observation is more accurate in a comparison to JUPEM specification.

79
4.2 TRANSFER COORDINATE

STN LATITUDE (N) LONGITUDE (E) ELEV (m)

ENG1 2⁰ 12' 28.23264" N 102⁰ 15' 01.08281" E 1.6953
ENG2 2⁰ 12' 25.26783" N 102⁰ 15' 01.86149" E 2.1593
ENG3 2⁰ 12' 26.93797" N 102⁰ 15' 00.17384" E 2.2226
FOT1 2⁰ 18' 13.69298" N 102⁰ 04' 45.39383" E 4.2754
FOT2 2⁰ 18' 09.67602" N 102⁰ 04' 41.62906" E 3.7504
HYD1 2⁰ 13' 14.10680" N 102⁰ 10' 32.34285" E 1.929
HYD2 2⁰ 13' 13.97042" N 102⁰ 10' 08.27598" E 2.3603

TRANSFERING POINTS IN MRSO (OLD)

STN NORTHING (N) EASTING (E) ELEV (m)

ENG1 244295.976 472712.689 1.6953
ENG2 244204.871 472736.605 2.1593
ENG3 244256.254 472684.539 2.2226
FOT1 254939.232 453706.268 4.2754
FOT2 254816.05 453589.724 3.7504
HYD1 245718.559 464410.954 1.929
HYD2 245715.607 463667.281 2.3603

80
TRANSFERING POINTS IN CASSINI-SOLDNER (OLD)

STN NORTHING (N) EASTING (E) ELEV (m)

ENG1 -56709.63 34308.552 1.6953
ENG2 -56800.693 34332.631 2.1593
ENG3 -56749.402 34280.474 2.2226
FOT1 -46100.906 15283.576 4.2754
FOT2 -46224.298 15167.266 3.7504
HYD1 -55301.903 26004.618 1.929
HYD2 -55306.191 25260.988 2.3603

4.3 RESULT FOR GPS HEIGHTING.

BASE: Tebong and Engine 3.

Ellips.
Station Latitude Longitude Ht.(m)
BM01 2 ° 13' 27.5167" N 102° 14' 30.3126" E 3.133
BM02 2° 15' 15.7985" N 102° 15' 15.9381" E 7.1107
BM03 2° 17' 04.3066" N 102° 15' 44.1180" E 9.9287
BM04 2° 17' 30.9943" N 102° 15' 46.1915" E 11.7103
BM05 2° 17' 55.7352" N 102° 15' 55.3748" E 13.18935
BM06 2° 18' 31.6720" N 102° 15' 34.9432" E 14.52605

Station Ortho. JUPEM true Diff.

Ht.(m) value (m) (m)
BM01 2.087 3.44 1.353
BM02 6.043 7.017 0.974
BM03 8.862 10.298 1.436
BM04 10.649 11.66 1.011

81
 BM05 12.124 13.027 0.903
BM06 13.493 15.333 1.84

BASE: BM01

Ellips. Ortho
Station Latitude (N) Longitude (E) Ht. (m) .Ht. (m)
BM02 2 °15' 15.783895" 102°15' 15.933285" 7.31455 6.247
BM03 2°17' 4.30158" 102° 15' 44.137955" 10.578 9.511
BM04 2°17' 30.979175" 102° 15' 46.1881" 11.89955 10.838
BM05 2°17' 55.717205" 102° 15' 55.39548" 13.1833 12.118
BM06 2° 18' 31.65723" 102° 16' 34.94623" 14.9181 13.813

BASE: BM06 (Checking Value)

Ellips. Ortho.Ht.
Station Latitude (N) Longitude (E) Ht. (m) (m)
BM01 2° 13' 27.5313" 102° 14' 30.3095" 2.7294 1.683
BM02 2 °15' 15.7984" 102° 15' 15.9360" 7.0011 5.933
BM03 2 °17' 04.3155" 102° 15' 44.1323" 10.2463 9.18
BM04 2 °17' 30.9938" 102° 15' 46.1893" 11.6202 10.599
BM05 2 °17' 55.7311" 102° 15' 55.4000" 12.7439 11.678

82
CHECKING VALUE OF ORTHOMETRIC HEIGHT FOR BASE BM01 AND BM06

Diff. of Ortho.
Ortho. Ht. Ht.
Station Base: BM01 Base: BM06
BM02 6.247 5.933 0.314
BM03 9.511 9.18 0.331
BM04 10.838 10.599 0.239
BM05 12.118 11.678 0.44

DIFFERENCE IN ORTHOMETRIC HEIGHT WITH JUPEM VALUE

Observation Observation -
Point (diff) JUPEM (diff) JUPEM
BM01 - BM02 3.956m 3.577m 0.379m
BM02 - BM03 0.974m 3.281m 2.307m
BM03 - BM04 1.787m 1.362m 0.425m
BM04 - BM05 1.475m 1.367m 0.108m
BM05 - BM06 1.369m 2.306m 0.937m

DIFFERENCES OF THE ORTHOMETRIC HEIGHT FOR EACH BENCHMARK BASED ON

DIFFERENT REFERENCE POINT

Base: Tebong and Engine3 Base: BM01 Diff.

Ortho. Ht. Ortho. Ht.
Station Ellips. Ht. (m) Ortho. Ht. (m) Ellips. Ht. (m) (m) (m)
BM02 7.1107 6.043 7.31455 6.247 0.204
BM03 9.9287 8.862 10.578 9.511 0.649
BM04 11.7103 10.649 11.89955 10.838 0.189
BM05 13.18935 12.124 13.1833 12.118 0.006

83
BM06 14.52605 13.493 14.9181 13.813 0.32

WORKFLOW

- In first processing, we select Tebong and ENG3 as reference point and make processing
using SKI-Pro software. After processing, we get value heighting in ellipsiodal and then
make transformation to orthometric height using myGeoid software and make
comparison between JUPEM value and observer value.
- From the result, we can see that the value are difference between JUPEM and observer.
Based on the tolerance from JUPEM, difference must be less than 10cm. For example,
at station BM1, the calculation such as :

Station Ortho. JUPEM true

Ht.(m) value (m) Diff. (m)
BM01 2.087 3.44 1.353
- In second processing, BM01 are selected as the reference point and then process to get
the value of ellipsoidal height for each BM and then transform to orthometric height.
- BM06 also are selected as reference point for process to checking value of each
benchmark.
- After that, compare the orthometric height of each benchmark according different
reference point.

ANALYSIS.

From this result, we get analyse that the benchmark at station 4 has fulfill the condition. The
tolerance difference for this benchmark below than 0.1m. the difference is 0.006m. That
means, although the heighting transfer far from the reference point, it stills give the allowed
tolerance sometime the heighting transfer from nearest benchmark.

For the second point, after that analysis we know that GPS heighting cannot use randomly.
But, in the real survey job, GPS can use according to time taken for processing and make
sure that the ambiguity status properly checking first.

84
 CONCLUSION

As a conclusion, this practical give some learning and skills and experience to
student in conducting The Global Positioning System (GPS) control project from all
elements such as planning, field work, processing and others.
GPS Control Network Survey is done to coordinate a GPS control network survey.
There are four tasks of fieldwork that had been done in this practical, which are network
test, baseline test, transfer control network survey and survey GPS heighting . For this
task, we had practiced for the Network Test that we were required to choose the best
monument to used in Baseline Test. Then, Baseline Test to calibrate the GPS equipments
Calibration Test were done to test the instrument whether it in a good condition or not
referring to the JUPEM requirement which the tolerance must be ± 10 mm. Control
network survey is to establish a control network based on the proven monuments, and to
establish local control point for engineering, photogrammetric and hydrographic survey.
Last is to transfer heights from BM to another BM (Benchmark). The difference value
will determine the error for each BM.
For the processing, we were exposed about the new software as Topcon Tools
Software, Leica SKI –Pro Software, and GNSS Solutions Software. These software are
very important in data processing and all of the software plays their own roles to produce
the output process and analyze. Before proceed to use the these software, we have to
make sure all the data were convert into Rinex format to make easily process in all of the
software.

As the overall we can say that The GPS Control Network Survey is one of the
techniques used in establishing control network that has many advantages compared to
other techniques. It is easy to set up, observation is done by the equipment itself, and it
used less equipment. It is more precise and accurate as it gave a value with accuracy up to
centimeters. It is also less time consuming.

85
 Comment

For this project we have taken some measure into consideration but somehow there are still some
problem occurred during observation such as do not know the specific way to measure antenna
height and measurement is less than the time specify. For example there are still a couple of
group that do not meet the standard of GPS measuring time for network analysis which has been
agreed to be for about 3 hours. This might occur due to miscommunication between groups and
some group that do not understand the work specification thoroughly. These lead to incorrect
data during data combination with the entire groups. As a group we figure that, for any big
project to be able to run smoothly is with proper planning.

There are no problems that occur to our group during recce and field work. We have understand
completely on how to handle all the three GPS receivers and how to conduct it. The
configuration has been going on find and the time setting for each session of works is enough for
processing job.

During processing there are also a couple of things that need to be taken into consideration
because there some GPS software that is really confusing particularly when entering the antenna
height. In some cases the antenna height need to be edited because the height entered is not
vertical height but slant. These problems often occur particularly when using Topcon receiver.

During analyses is when we can actually conclude the important things that we have taken
during fieldwork because it is moderately related to the final ouput. We also understand the role
of frequencies in data broadcasting as it relate to the error in reading. And we can finally
understand the need to specify the elevation mask for data collecting as it affect the number of
satellite available for the job as it help the accuracy of the data.

Overall we have completed both tasks successfully.

86
APPENDIX

87
 GPS Observation at Bukit China

GPS Observation at Tanjung Kling , Jetty Tanjung Beruas

Baseline Test MITC Ayer Keroh, Melaka

88