Iot Applications and Design Guide Ebook MWJ
Iot Applications and Design Guide Ebook MWJ
Iot Applications and Design Guide Ebook MWJ
OCTOBER 2018
S P O N S O R E D B Y
Table of Contents
3
Introduction
Patrick Hindle
Microwave Journal, Editor
7
Evolution of The IoT as a Service
Cees Links
Qorvo
27
Distributed Wi-Fi: How a Pod in Every Room Enables
Connected Smart Homes
Cees Links
Qorvo
2
Introduction
3
Addressing The Challenges Facing
IoT Adoption
Kailash Narayanan
Keysight Technologies, Santa Rosa, Calif.
T
he Internet of Things (IoT) phenom- cloud analytics will be the most successful at
enon—ubiquitous connected things monetizing a large portion of the value in IoT.
providing key physical data and further Low power, wide area (LPWA) IoT technolo-
processing of that data in the cloud to gies open up possibilities for service providers.
deliver business insights— presents a huge op- Knowing the location of pets and vehicles, track-
portunity for many players in electronics and ing valuable personal belongings, monitoring
software, including chipset vendors, device de- utility usage, obtaining real-time data on the
velopers, OEMs, manufacturers, equipment ven- health of crops and livestock, employee fatigue
dors, network operators and end-to-end solu- and machine status are useful for individuals and
tions providers. Many companies are organizing businesses.
themselves to focus on IoT and the connectivity A typical smartphone contract delivers rough-
of their future products. ly five cents per MB of data. Assuming an IoT
application uses 100 KB per month, and a user is
CHALLENGES willing to pay a modest 10 cents per month for
For the IoT industry to thrive, three items are these new IoT applications, that’s already better
crucial: a viable business model, a robust con- business for an operator. Delivering $1 per MB
nectivity topology and reliable devices. This arti- is 20x more revenue than a typical smartphone
cle discusses these, focusing on the design chal- contract for the same amount of data consump-
lenges that must be overcome to make reliable tion. While many IoT applications may attract
devices. Challenges vary depending on the IoT modest revenue, some can attract more than
application. While cost is a major factor in con- $10 per month. For little burden on the existing
sumer applications (e.g., wearables and home communication infrastructure, operators have
automation), industrial IoT applications (e.g., the potential to open up a significant source of
smart grids, connected cars and transportation) new revenue using LPWA technologies. Clearly,
require unfailing reliability, longevity, security it is important to understand the value chain and
and the ability to operate devices with little or business model for the IoT application.
no human intervention.
Connectivity Topology
The Business Model Figure 1 shows a simple IoT network model,
End-to-end solution providers operating in consisting of a device layer containing “things”
vertical industries and delivering services using with sensors and actuators that capture or initi-
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4
Bluetooth LE
ZigBee
Z-Wave
802.11ah/p
NFC/EMV
“Things” with
Sensors/Actuators
Industrial Industrial Data Center
Short Range
Gateway Long Range
Connectivity
(ZigBee) Connectivity (LTE)
Server Cluster
Internet
Home (Service Provider) Business
Applications
(Billing, CRM)
Consumer Gateway
I/O
Memory
T
he concept of connectivity that is at the heart What is different today is that advances in
of the Internet of Things (IoT) is not new. The technology are moving us ever closer to realiz-
ing the full potential of the IoT to help manage
X10 communications protocol, which enabled our lives and enterprises. These innovations are
wireless control of in-home devices, made its enabling low power, smart sensors that can ob-
debut in the 1970s. We are also long accustomed to au- serve, learn and make decisions to create better,
tomatic garage door and car door openers and—more more efficient environments. Another new de-
velopment is that we understand that consumers
recently—smartphone applications that allow us to re- want more than just a collection of connected
motely manage the electronic devices in our homes. devices. They want to experience the benefits of
the IoT as a service and without the challenge of
having to research, locate, purchase, install and
maintain a sensor network themselves.
IoT TECHNOLOGIES
To delve into the future of the IoT as a ser-
vice, let’s first look at the foundational technolo-
gies that support IoT content and how they are
evolving to create smarter, more fully connected
environments. The IoT requires connectivity at
several levels: wide area networks (outdoor), lo-
cal area networks (indoor) and personal area net-
works (wearable and mobile). The technologies
that are enabling this today include LTE, Wi-Fi
and Bluetooth.
LTE for Outdoor Wide Area Networks —
LTE is the modern high speed wireless commu-
nications standard for mobile phones and data
terminals that supports 4G services. The tech-
nology is easily deployed and optimizes network
connectivity by using separate radio links for
the device-to-tower uplink and tower-to-device
downlink. LTE is important because it enables
more efficient use of the ever-limited spectrum
available to connect low power IoT devices with
back-end systems.
Wi-Fi for Indoor Local Area Networks — Wi-
Fi, the 802.11x IEEE standard, is most commonly
used for wireless networks in the home and within
businesses or organizations. Its ability to transmit
data at very high rates also drains the battery and
reduces operating time, which results in users
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7
IoTivity
AllJoyn
(Open Home Kit Agile IoT
Application Layer (AllSeen
Interconnect
Brillo
IOS LiteOS
Alliance)
Consortium)
Weave
Communication Layer
(RF Standards)
s Fig. 1 Ensuring interoperability among competing standards is essential to the successful adoption of the IoT.
having to charge their devices frequently. (Hence, the rise low cost, ultra‐low power devices and nodes. It is already
of technologies such as Bluetooth and Zigbee® that support anchored in the consumer electronics world with Zigbee
small, low power IoT devices, where batteries can last for RF4CE and Zigbee Green Power features. Zigbee Green
years.) Power minimizes power demand with self‐powered energy
Bluetooth for Mobile or Wearable Personal Area Net- harvesting. Zigbee RF4CE defines a low power, low latency,
works — Bluetooth is a low power, short‐range commu- RF remote control network for two-way, device‐to‐device
nications technology primarily designed for point‐to‐point control applications that do not require a full‐featured wire-
communications between wireless devices. While it has less mesh network.
been used most often for applications in keyboards, mice, Thread — A Zigbee 3.0 challenger, Thread entered the
smartphones and headsets, Bluetooth is becoming more market as both a mesh networking protocol and working
network capable, in the form of Bluetooth Low Energy group founded by Google subsidiary Nest.
(BLE), which supports lower power consumption and can BLE — BLE devices consume significantly less power
directly access the internet. than traditional Bluetooth devices and can access the Inter-
At the heart of the IoT’s future are small, “smart,” lower net directly through IPv6 over low power wireless person-
power sensors and devices. Foundational connectivity tech- al area networks (6LoWPAN) connectivity. These features
nology is evolving to address the networking requirements make it well suited for IoT devices that operate on small
for low power, just as chip technology is advancing to sup- batteries or for energy-harvesting devices.
port multiple communications protocols within the same de-
vice. These newer options include: THE MOVE TO SMART DEVICES
Long Term Evolution for Machines (LTE-M) — LTE cate- In addition to competing standards at the communica-
gory M1 (LTE-M) is a low power version of LTE that enables tions layer, there is industry competition at the application
IoT devices to connect to a 4G network directly. It supports layer (see Figure 1). Both pose significant challenges for
significantly extended battery life—longer than 10 years— anyone who is developing, selling or purchasing products
through a power savings mode where devices awaken only for the home. Consumers who wish to have a smart home
to transmit or receive data. LTE-M eliminates the need for are faced with having to decide between Wi-Fi, Bluetooth,
full-featured LTE devices while still providing cellular-quality Zigbee and other technologies. Companies that develop
coverage. and market components for the home risk millions of dol-
Zigbee® — This low cost, low power, wireless, mesh net- lars in development and customer support costs if they
work protocol is based on the IEEE 802.15.4 standard and make the wrong choice.
is the most common protocol in the low power networking Many IoT device discussions use the terms “smart” and
market, with a large installed base in both industrial envi- “connected” interchangeably. Many devices called “smart”
ronments and home devices. Zigbee 3.0 is the foundation today are only slightly more capable than those launched
for the IoT and “smart home” solutions, with redundant, decades ago. They are mostly stand-alone units that require
8
human action to be turned on and off. For example, while a and purchase equipment and try to guess which wireless
home security sensor may be “connected” and detects that technology standard to use, the consumer simply relies on
no one is in the home, it does not interact with the lighting the providers of the services they already use, such as inter-
sensor to turn off the lights or with the heating system to net access, security and entertainment. Their routers, mo-
turn down the thermostat. dems and set-top boxes are already in the home, and cus-
A smart device and application can analyze incoming tomers are accustomed to paying a monthly bill for these
data and make a decision to control or activate a device services. Consumers can select the services they want and
without human intervention. In the case of the smart home control them through a single smartphone app.
environment, a network of devices can sense who is in the Retail organizations that provide some home services,
home, where they are in the home and learn what “nor- such as Wal-Mart, Home Depot, Costco and others, could
mal” activity is at a particular day and time. Using this intel- easily enter this market. Large security firms and integrators
ligence about the residents, the network makes decisions could market an entire suite of services as a unified pack-
about whether to lock doors and windows; turn on or off age.
the heater, air conditioner, lights or entertainment system;
or activate the security system. To be considered “smart,” a Applications and Benefits
device must have three capabilities: The benefits of the SHaaS are limited only by the imagi-
• Connect to and exchange data with other smart or con- nation. Here are a few examples:
nected devices in the home Comfort, Cost Savings and Sustainability — If a family
• Recognize what goes on in the home and learn what is were watching a movie on a cold winter night, a smart home
normal, beyond being programmed for a certain func- system would turn off the lights and turn down the heat in
tion at a certain time the empty parts of the home. Power-consuming devices
• Use a single integrated application on a smart phone or that are on but not in use would also be turned off. The sys-
other web-connected device to manage all the functions. tem would lower the temperature for sleeping during the
night and begin to raise it again before the family awakens
THE SMART HOME AS A SERVICE and begins the day. If the home network recognizes that
While the IoT ultimately will affect every aspect of how the family is away on vacation, it would disconnect devices
our world operates, the home environment provides an ex- that consume standby power.
cellent example of what is emerging as the future of the IoT Connecting the water heater to a smart sensor would
as a service. Consumers are making it clear that they want allow leaks to be detected early. The smart sensor would
more than a collection of sensors in their homes. They are alert the homeowner and also control the power and water
not really seeking to own smart technology, rather they are systems connected to it. With smart sensors, homeowners
looking for smart services and the ability of those services can remotely run their dishwashers and appliances. Prob-
to help manage their lives. lems would automatically be detected and relayed to a re-
The Smart Home as a Service (SHaaS) is the next phase pair service. Home energy use and repair costs would be
of the home IoT evolution. SHaaS is a collection of services reduced and natural resources conserved. Insurance com-
where devices, sensors and applications work together panies already are noting smart home applications that pro-
without human interaction. This network makes intelligent vide early warning of water leaks, heating system defects
decisions that render homes more comfortable, safe and and fire, which can reduce repair, renovation and replace-
energy efficient. SHaaS solutions can reduce the number of ment costs.
sensors required in the home, and a single sensor can be Senior Lifestyle — Many of us are living longer and want
used for a variety of applications. For example, a motion to remain independent. The SHaaS for seniors can help
sensor can be used for the security system, light control, keep us safe and comfortable in our own homes without
managing the temperature and controlling entertainment feeling that we are being watched by cameras. To do so, a
and senior lifestyle systems. There are four components of limited number of small, battery-powered sensors for mo-
a SHaaS: tion detection and door opening and closing, strategically
• A network of sensors in the home provides a general in- placed throughout the residence, would “observe” activi-
dication of when and where movement occurs, the envi- ties and collect data. When something out of the ordinary
ronmental conditions and whether the home is secure or occurs, the system would automatically notify family mem-
there are issues, such as a leak bers, a friend or emergency personnel.
• The information derived from these sensors is wirelessly Fitness and Healthcare — Wearable lifestyle and fit-
collected by a local hub (e.g., gateway or set-top box) ness technology would integrate many more data points,
and securely transmitted to an intelligent cloud service including from sensors in the home, and help ensure proper
that collects and analyzes the data and sends alerts to nutrition and rest based on our health goals and medical
family members when it detects changes histories.
• A central management app enables the consumer to
manage the network using a single user interface on a INDUSTRIAL IoT
smartphone or any web-connected device The IoT is destined to have a profound impact, well be-
• The service provider is easily able to handle customer yond the home environment. It will transform virtually all
support, billing, subscriber management, software and industries, from hospitality and retail to automotive, agri-
service upgrades and changes. culture and healthcare, altering the way that municipalities
and public services operate. For example, smart cities of
A SHaaS eliminates the need for the consumer to be
the future will likely leverage the IoT for city lighting man-
technology-savvy. Rather than having to research, select
9
agement, traffic flow monitoring and control, emergency Cees Links is a pioneer of the wireless data industry and the man who
services deployment and natural resource management. led the team that created and popularized Wi-Fi. Cees was the founder
and CEO of GreenPeak Technologies, a Smart Home and IoT radio
In manufacturing, the increasing complexity of just-in- communications semiconductor company, now part of Qorvo. After
time supply chain processes will benefit from IoT appli- Qorvo’s acquisition of GreenPeak in 2016, Cees has become the Gen-
cations that enable more precise forecasting, inventory eral Manager of the Wireless Connectivity business unit in Qorvo. He
tracking and delivery of needed parts, as well as better col- was recognized as Wi-Fi pioneer with the Golden Mousetrap Lifetime
Achievement award.
laboration between suppliers and customers. Biosensors in
the healthcare environment will speed testing and accurate
diagnosis of a wide variety of conditions. They will also
monitor the ecosystems related to wellness, such as water
quality, drug and food safety.
jfwindustries.com
10
Simulation Speeds NB-IoT Product
Development
Takao Inoue and David Vye
AWR Group, NI, El Segundo, Calif.
A
nalysts from technology research firm ware. VSS test bench examples are presented,
Gartner are predicting a population including NB-IoT signals operating in the same
of over 26 billion devices—excluding band as an LTE signal and in the guard band of
smartphones, tablets and comput- an LTE signal.
ers—connected to the internet of things (IoT)
by 2020. This volume of connected devices will SYSTEM REQUIREMENTS
require massive support from existing wireless In release 13, the 3GPP specified a new radio
networks. Among the mobile IoT (MIoT) technol- air interface for MIoT applications. It focuses on im-
ogies to be standardized by the 3rd Generation proved indoor coverage, low-cost devices (less than
Partnership Project (3GPP), narrowband IoT (NB- $5 per module), long battery life (more than 10 years),
IoT) represents the most promising low power massive connectivity (around 50,000 connected
wide area network (LPWAN) radio technology, en- devices per cell) and low latency (less than 10 ms).
abling a wide range of devices and services to be NB-IoT will enable operators to expand their
connected using the cellular telecommunications wireless services to applications such as smart
bands (see Figure 1). metering and tracking and will enable nascent
This article presents an overview of NB-IoT opportunities such as “smart cities” and eHealth
requirements, how they compare with LTE and infrastructure. NB-IoT will efficiently connect
the resulting challenges for component devel- these many devices using the existing mobile
opment. The use of simulation tools for system networks, adding small amounts of fairly infre-
analysis and design is demonstrated using NI quent two-way data, securely and reliably. The
AWR Design Environment, specifically, Visual standard utilizes 180 kHz user equipment (UE)
System Simulator™ (VSS) system design soft- bandwidth for both downlink and uplink and can
operate in three different deployment modes.
As shown in Figure 2, these mode are:
Gbps Short
Distance Cellular Standalone operation, in which a GSM opera-
tor replaces a 200 kHz GSM carrier with NB-IoT,
Mbps UMTS, HSPA, LTE, LTE-A
Wi-Fi re-farming dedicated spectrum in, for example,
Zigbee GSM EDGE radio access network (GERAN) sys-
LPWA
kbps Bluetooth tems. This is possible because both the GSM car-
LoRa, SigFox, NB-IoT, LTE-M rier’s bandwidth and the NB-IoT bandwidth, in-
bps clusive of guard band, are 200 kHz. NB-IoT inside
10 m 100 m 1 km 10 km an LTE carrier, where the operator allocates one
of the 180 kHz physical resource blocks (PRB) to
s Fig. 1 Universe of networking technologies.
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11
NB-IoT. The NB-IoT NB-IoT will heavily utilize LTE technology, including
air interface is opti- downlink orthogonal frequency division multiple access
mized for harmoni- (OFDMA), uplink single carrier frequency division multiple
200 kHz
(a) ous coexistence with access (SC-FDMA), channel coding, rate matching and in-
LTE without compro- terleaving. This is reducing the time to develop specifica-
mising the perfor- tions and NB-IoT products by LTE equipment and software
200 kHz mance of either. vendors. However, developing robust, low-cost and pow-
(b) Guard-band deploy- er-efficient IoT devices that handle low data rates with large
ment, utilizing the un- area coverage is a departure from component design ef-
used resource blocks forts driven by the different system requirements of cellular.
200 kHz
(RB)within an LTE car- As the following examples illustrate, RF system simulation
(c) rier’s guard band. can help solve these challenges and support the design
s Fig. 2 Deployment modes for NB-IoT: theTable 1 shows
specifications
and analysis of the UE modules, antennas, RF front-ends
and wireless networks that will co-exist with NB-IoT and LTE
standalone GSM (a), in-band LTE (b) and
guard-band LTE (c). for NB-IoT, which signals.
are quite different
than the specifications for existing cellular technology. IN-BAND IoT SIMULATION
Where cellular technologies require large bandwidth with The VSS project shown in Figure 3 simulates the op-
high data rates and low latency at the expense of lower eration of NB-IoT inside an LTE carrier. The NB-IoT uplink
device battery life, IoT requires robust data transmission signal is configured as in-band, narrowband physical up-
with significantly lower data rates, long range coverage link-shared channel (NPUSCH) format 1 and compliant with
and long device battery life. While LTE uses bandwidths the 3GPP release 13 specification. In this example, the NB-
greater than 1.4 MHz, IoT communication can suffice IoT signal is placed in an unused RB within the LTE band.
with kHz bandwidths. Given these differences, using the The available NB-IoT examples in VSS enable studying in-
existing GSM and LTE systems for IoT wastes spectrum band and guard-band operation modes.
and data rate. The introduction of a narrowband channel, The NB-IoT uplink supports both multi-tone and sin-
such as 3.75 kHz, quadruples the number of connections gle-tone transmissions. Multi-tone transmission is based on
in LTE’s traditional 15 kHz subcarrier spacing. Device cost SC-FDMA, with the same 15 kHz subcarrier spacing, 0.5 ms
is another factor differentiating mobile devices designed slot and 1 ms sub-frame as LTE. SC-FDMA is an attractive
for voice, messaging and high speed data transmission alternative to OFDMA, especially in uplink communications.
from NB-IoT applications that require low speed and re- The lower peak-to-average power ratio (PAPR) greatly ben-
liable data transfer. Many NB-IoT use cases require a low efits the mobile terminal in transmit power efficiency, which
device price to be viable, as well as consideration of in- extends battery life and reduces the cost of the power ampli-
stallation and potential risk of theft. fier. Single-tone transmission supports two subcarrier spac-
ing options: 15 and 3.75 kHz. The additional 3.75 kHz option
TABLE 1 uses a 2 ms slot and provides stronger coverage to reach
NB-IoT SPECIFICATIONS challenging locations, such as deep inside buildings, where
signal strength can be limited. The 15 kHz numerology is
NB-IoT identical to LTE and, as a result, achieves excellent coexis-
Deployment Standalone GSM, In-Band LTE, Guard- tence performance. The data subcarriers are modulated us-
Band LTE ing π/2 binary phase shift keying (BPSK) and π/4 quadrature
Coverage 164 dB phase shift keying (QPSK) with phase continuity between
(Maximum Coupling Loss) symbols, which reduces PAPR and allows the power amplifi-
Downlink OFDMA, 15 kHz Tone Spacing, TBCC, ers to operate more efficiently (saturated). The number of 15
1 Rx kHz subcarriers for a resource unit can be 1, 3, 6 or 12, sup-
Uplink Single Tone: 15 kHz and 3.75 kHz porting both single-tone and multi-tone transmission of the
Spacing, SC-FDMA: uplink NB-IoT carrier, with a total system bandwidth of 180
15 kHz Tone Spacing, Turbocode kHz (up to 12, 15 kHz subcarriers or 48, 3.75 kHz subcarriers).
Bandwidth 180 kHz The NB-IoT uplink physical channel includes a nar-
Highest Modulation QPSK
rowband physical random access channel (NPRACH)
and NPUSCH. The NPRACH is a new channel de-
Link Peak Rate (DL/UL) DL: ~30 kbps UL: ~60 kbps signed to accommodate the NB-IoT 180 kHz uplink
Duplexing HD FDD bandwidth, since the legacy LTE PRACH requires a
Duty Cycle Up to 100%, No Channel Access 1.08 MHz bandwidth. Random access provides initial ac-
Restrictions cess when establishing a radio link and scheduling request
MTU Maximum PDCP SDU Size 1600 B
and is responsible for achieving uplink synchronization,
which is important for maintaining uplink orthogonality in
Power Saving PSM, Extended Idle Mode DRX With Up NB-IoT. The NPUSCH supports two formats. Format 1 car-
To 3 h Cycle, Connected Mode DRX With
Up to 10.24 s cycle ries uplink data, supports multi-tone transmission and uses
the same LTE turbo code for error correction. The maxi-
UE Power Class 23 or 20 dBm
mum transport block size of NPUSCH format 1 is 1000 bits,
which is much lower than that in LTE. Format 2 is used for
12
TP
ID = NB-IoT_Rx
BER Measurement
TP TP
ID = NB-IoT_OUT SUBCKT ID = RxBits
SUBCKT AWGN
COMBINER NB-IoT UL
NB-IoT UL RX
TSIGE MB CRC BER
TxBits
TxBits
Throughput Estimation
TP TP TP TP
ID = MOD_IQ ID = TxBits ID = DEMOD_IQ ID = GRC
LTE UL Source
SUBCKT
TP
ID = LTE_OUT
LTE UL
TSIG 1
PD MS
2 3
1 2 1 2 1 2 1 4
3 2
PUSCH CRC Turbo Rate Matching Scrambler Modulation Transform 3
Data Encoding Mapper Precoder
Resource Element
Mapper and
Frame Assembler
Reference Signal
NPUSCH Data
–140
–150
bit stream out of the encoders. For each code word, all the
–160
bits transmitted on the physical uplink shared channel in one
–170 sub-frame are then scrambled with a UE-specific scrambling
–180 sequence prior to the modulation mapping, which has been
–190 selected by the system developer through the configuration
–200 options.
3.490 3.495 3.500 3.505 3.510
SC-FDMA can be interpreted as a linearly pre-coded
Frequency (GHz)
OFDMA scheme, in the sense that it has an additional dis-
crete Fourier transform (DFT) processing step preceding
s Fig. 5 NB-IoT and LTE spectra for the in-band mode.
the conventional OFDMA processing. A DFT is performed
by the transform pre-coder before the NPUSCH channel is
signaling hybrid automatic repeat request (HARQ) acknowl- multiplexed with the reference signal subcarriers (either sin-
edgements for narrowband physical downlink shared chan- gle- or multi-tone) by first mapping them to the appropriate
nel (NPDSCH) and uses a repetition code for error correc- physical resources and then to the orthogonal frequency-
tion. In this case, the UE can be allocated with 12, 6 or 3 division multiplexing (OFDM) symbols and slots within each
tones. The 6 and 3 tone formats are introduced for NB- frame. Much like OFDMA, SC-FDMA divides the trans-
IoT UEs that, due to coverage limitations, cannot benefit mission bandwidth into multiple parallel subcarriers, main-
from the higher UE bandwidth allocation. taining the orthogonality of the subcarriers by the addition
13
1 –100
Measured BER NB-IoT Tx
15 kHz SCMode = LTE Tx
–120 NB-IoT Rx
0.1 8 Ref. BER
Power (dBm)
BER
TP
ID = NB-IoT_Rx
SUBCKT BER Measurement
TP TP
ID = NB-IoT_OUT ID = RxBits
AMP_82
COMBINER SUBCKT
1 1 1 2
2
2 3 4 3
TxBits
Throughput Estimation
TP TP TP
ID-MOD_IQ ID = TxBits ID = DEMOD_IQ
LTE UL Source
–100
TP NB-IoT Tx
ID = LTE_Out LTE Tx
–120 NB-IoT Rx
1
Power (dBm)
PD MS –140
2 3
–160
(a)
–180
3
–200
3.490 3.495 3.500 3.505 3.510
Frequency (GHz)
(b)
s Fig. 9 Test bench with power amplifier (a) and guard-band mode spectra (b).
14
error rate (BER) (see Figure 6), block error rate (BLER),
throughput (see Figure 7) and the CRC error for each
block.
CONCLUSION
The NB-IoT standard specified in 3GPP release 13 lever-
ages the existing LTE network to support a future ecosystem
of low-cost IoT devices. While the use of the existing LTE in-
frastructure with relaxed performance requirements, due to
the lower data rates, will help offset some design challenges,
the need for low cost, increased coverage area and longer
battery life with sustained reachability introduces some dif-
ficult-to-achieve requirements. VSS and other system simu-
lation tools aid NB-IoT system development by simulating
designs pre-silicon, saving valuable time and effort bringing
these new products to market.n
15
Antenna Technologies
for the Future
Patrick Hindle
Microwave Journal Editor
T
raditional antenna technology has hit based on polymer materials that are then metal
its limits in many demanding commer- plated or on metallic materials (such as alumi-
cial and aerospace markets such as 5G, num or titanium) combined with advanced sur-
SATCOM, IoT and radar. But there are face treatments and surface plating. Using these
many companies developing new approaches processes, SWISSto12 manufactures and tests
and materials that could drastically improve an- aerospace qualified advanced RF products such
tenna performance and enable new applications as waveguides, filters, beamforming networks,
that were not previously envisioned because of antenna feed chains or array antennas.
these limitations. In this article, Microwave Jour- Their use of 3D printing allows for increased
nal looks at a sampling of these technologies flexibility in the manufacturing of complex prod-
that have come to our attention in the last cou- uct designs. This freedom can be used to pro-
ple of years. duce higher complexity RF components, which
often allows for better RF performance. Tradi-
3D PRINTED ANTENNAS tional machining technologies used to manu-
Recent advances in 3D printing or additive facture RF products are limited in their ability
manufacturing have enabled complex RF struc- to produce products with complex shapes. To
tures to be realized. The characterization of the circumvent this limitation, complex products are
materials used in 3D printing processes has often assembled out of a larger number of sim-
been shown to be critical in designing and accu- pler sub-components that are produced sepa-
rately predicting the performance of these struc- rately. SWISSto12’s 3D printing technology does
tures. Understanding the RF properties of the not have such constraints, allowing it to pro-
materials through characterization has led to the duce entire products in one single element that
development of novel structures that could not positively impact mass, cost, lead time, assem-
ever be realized with traditional manufacturing bly quality and RF performance. The use of 3D
techniques. 3D printing has also allowed manu- printing also allows for optimized weight reduc-
facturers to produce traditional antenna shapes tion. The technology has been demonstrated on
with less weight and at a lower cost. waveguide, filter and antenna components from
SWISSto12 SA is an offshoot from the Swiss C- to W-Band (4 to 110 GHz).
Federal Institute of Technology in Lausanne, As this technology is rapidly gaining maturity
Switzerland. The company has developed and acceptance among the aerospace indus-
unique products using 3D printing that are try, SWISSto12 has already delivered a variety
WWW.MWJOURNAL.COM/ARTICLES/29572
16
of prototypes to or-
ganizations in the
space and SATCOM
industries that have
been qualified for
use in airborne and
space environments
(a)
(the first commer-
cial programs will
Co-Polar Measurements
Cx-Polar Measurements be flying SWISSto12
Co-Polar MoM Simulations products in 2018).
Cx-Polar MoM Simulations
More complex and Elevation Normalized Gain 31.0 GHz
0
14.5 GHz integrated antenna
0
or payload structures –5.00
17
Backshell Feed TFT Radome
(Enclosure) Assembly Aperture Assembly Bezel
Control
Electronics
10
ple of the cross in the middle of the array, and a CT-scan
0
–10 showed the details of all of the fingers confirming the con-
–20 struction and working on full scale antenna structures.
–30
–40 METAMATERIAL BASED ANTENNAS
60
40 60 Metamaterials are made by arranging naturally occurring
20 40 materials in a specific pattern that produces an electromag-
Elev 0 20
ation –20 0
(°) –40 –40 –20
uth (°)
netic response that is not found in nature. The periodic struc-
–60 –60 Azim tures created are at scales that are smaller than the wave-
lengths of the phenomena they influence and can create
Fig. 4 Optisys Integrated Printed Antenna and signal pattern.
materials with negative indexes that control electromagnetic
energy in ways that cannot be done with natural materials. In
frequency and a set traditional active electronically scanned arrays (AESA), phase
of elevation patterns shifters embedded in control circuitry steer the beam direc-
across the frequency tion. Metamaterial-based AESAs can steer the beam without
band are shown in phase shifters, which reduces system complexity, eliminates
Figure 4. a source of power loss and simplifies waste-heat dissipation.
As covered in There are a couple of companies using unique metamaterial
the October 2016 structures developed for this application.
issue of Microwave Kymeta experimented with these structures for many
Journal, The MITRE years and discovered that the metamaterials could be used
Corporation is in- to form holographic beams that could link to satellites and
vestigating a new maintain the link while the antenna is in motion. Kymeta
generation of 3D mTenna™ technology (see Figure 6) is manufactured us-
printing to realize the ing a completely different process and components than
complex geometries both traditional antennas and phased array antennas.2 The
Fig. 5 A small test coupon of MITRE’s of wideband phased “metamaterial” in mTenna technology is a metasurface in
biaxial metamaterial created with a array and metama- a glass structure. Their glass-on-glass structure is manu-
Voxel8 multi-material 3D printer. terial designs using factured on the same production lines as LCD flat screen
commercial, low-cost, compact, desktop printers.1 Sam- televisions, making it suited for low-cost, high volume man-
ples of the 3D printed plastic and conductive ink printed at ufacturing. They use the thin film transistor liquid crystal as
room temperature were characterized over frequency. The a tunable dielectric. Instead of reflecting microwaves like a
polylactic acid (PLA) dielectric constant and loss tangent traditional dish antenna or creating thousands of separate
are found to be stable up to 18 GHz. The PLA internal ar- signals like a phased array, Kymeta uses a thin structure with
chitecture was varied to achieve lower effective dissipation tunable metamaterial elements to create a holographic
factors, which extends usefulness to high frequency appli- beam that can transmit and receive satellite signals.
cations. Microstrip line samples were fabricated with simu- They use software to steer the antenna, eliminating the
lated and measured insertion loss data validating the high need for mechanical gimbals to point the antenna toward a
conductivity through mmWave frequencies. A 3D printed satellite. The antenna does not require active phase shifters
monopole Wi-Fi antenna was built and tested, showing or amplifiers. Key features of the approach:3
good performance and agreement with simulations. 1. Transmit and receive via a single aperture
MITRE also has developed a wideband phased array 2. Wide angle scanning and excellent beam performance
concept that has a complex metamaterial design. It is based 3. Electronically controlled pointing and polarization
18
4. Extremely low power consumption small lightweight form factors. Their technology can switch
5. First electronically scanned antenna designed for mass in less than 1 μs, has beam shaping and multi-beam capa-
production. bilities and can steer in both directions, providing near full
Traditional satellite dishes are heavy, large, expensive, hemisphere coverage. It operates at 24 GHz and has an op-
consume a lot of power and have mechanical gimbals for erational range of 3.4 km with a field of view ≥120 degrees
steering, which have prevented or limited their adoption azimuth and 80 degrees elelvation with a range resolution
on most mobile platforms. Kymeta’s mTenna technology of 3.25 m and velocity resolution 0.9 m/s.4
provides software-enabled, metamaterials-based, electron- LiDAR and cameras have limited range and do not oper-
ic beamforming satellite solutions that are flat, lightweight, ate reliably in adverse weather, while traditional radar in this
small and use software to steer instead of mechanical parts. sector has inadequate resolution. Echodyne’s radar vision
This technology is being used to deliver internet connec- platform represents a new category of sensor technology
tivity to industries that have historically been inaccessible or to enable many autonomous vehicles from drones to cars.
difficult for the satellite industry to address, such as rail, bus Their high performance imaging radar is viable and afford-
and automotive. Also, the maritime and aviation markets able on commercial and small platforms, including all types
have struggled to implement satellite technology broadly of autonomous and unmanned vehicles and machines.
across smaller vessels and aircraft.
A second company, Echodyne, has developed metama- FRACTAL BASED ANTENNAS
terial arrays for radar using similar antenna technology to A fractal is “self similar” complex pattern built from the
Kymeta but optimized for radar applications. Echodyne’s repetition of a simple shape. A fractal element antenna is
radar vision platform represents a unique sensor technolo- shaped using fractal geometry. The inherent properties of
gy that combines the all-weather, long range and ground- fractals can enable high performance antennas that can be
truth measurements of radar with high resolution imaging 50 to 75 percent smaller than traditional antennas. Typical
capabilities (see Figure 7).4 Radar vision consists of high advantages are increased bandwidth, better multi-band
performance agile imaging radar hardware combined with performance and higher gain. Fractal antennas can be more
computer vision-like software for classification, recognition reliable and lower cost than traditional antennas because
and perception. antenna performance is attained through the geometry of
Their metamate- the conductor, rather than with the accumulation of sepa-
rial based, electron- rate components or separate elements that can increase
ically steered array the complexity, potential points of failure and cost.
radars operate in the Fractal Antenna is a small company that produces frac-
same way as tradi- tal versions of many existing antenna types, including di-
tional designs, pro- pole, monopole, patch, conformal, biconical, discone, spi-
viding high resolu- ral and helical, as well as compact variants of each that is
tion data at any time made possible through fractal technology. They were the
and in any weather. first to demonstrate wideband RF invisibility cloaking and
Like Kymeta’s ap- used fractal shaped metal patterns on a mylar sheet. In their
proach, they can be demonstration, a signal from 750 to 1250 MHz was atten-
produced in high vol- uated by only a fraction of a dB over the same 50 percent
Fig. 7 Echodyne’s radar vision unit ume, at commercial bandwidth that would normally be attenuated by 6 to 15
next to an iPhone. price points and in dB without the cloak (see Figure 8).5,6
At EDI CON USA 2016, Dr. Nathan Cohen
Uncloaked Response of Fractal Antenna gave a session and demon-
15 stration of their unique RF/microwave cloaking
10 and deflection technology using fractal struc-
5
Gain (dB)
0
tures. Over a broad band, 2.5 to 3 GHz, he
–5 created a Waldo (window around a wall) that
–10 channeled the RF energy around a barrier
–15 (the “wall”) using an array of closely packed
–20
fractal-shaped resonators that was wrapped
500
600
700
800
900
1000
1100
1200
1300
1400
1500
19
tenna booster can low loss device. Due to their silicon IC construction, PSiDs
be picked and can be reproduced with high precision for the mass market
placed like oth- at low cost. They have high power handling and, unlike RF
er surface-mount MEMS, can be “hot” switched.
components onto PSiAn uses either single or multiple PSiDs to perform
a PCB for low cost azimuth and elevation beam steering. The PSiDs are
assembly (see Fig- mounted on RF PCBs and use transmission lines to link
ure 9). Aimed at the device ports to traditional RF and antenna technolo-
Fig. 9 The CUBE mXTEND™ antenna mobile devices and gies, such as LNAs, PAs, printed feeds, lenses and reflec-
booster from Fractus Antennas (5 mm3). IoT applications, it tors to produce efficient smart antennas with steerable
is made with met- narrow beams. Potential applications of PSiAn plasma
6.0 100 alized ceramic lay- antennas include: small cell backhaul at V-Band (60 GHz),
ers that use fractal gigabit wireless LAN (e.g. WiGig), intelligent transport
Total Efficiency (%)
5.0 80
shapes designed to systems (ITS) at 63 GHz and vehicle radar (77 GHz).
4.0 VSWR 60 meet different de- The company recently introduced an antenna that re-
VSWR
Efficiency
3.0 40 sign requirements. duces the cost of a 5G base station by up to 50 percent
2.0 20 Miniature chip an- by eliminating phase shifters, reducing and consolidating
tennas are not new, amplification and reducing computation. The technology
1.0 0
0.90 1.20 1.50 1.80 2.10 so what is unique does not need calibration and can handle high-power, hav-
Frequency (GHz) here is the multiband ing been tested up to 40 W. The company has shown the
capability with a sin- technology in a variety of scenarios, including a 360 degree
Fig. 10 VSWR and efficiency for gle device. While field of view, beamforming and steering, 28 GHz, 5 W, 16
5 band mobile antenna from Fractus conventional minia- dBi gain PSiAN, useful for pole mounted small cells, indoor
Antenna.
ture chip antennas small cells—also on a vehicle and a high-power, long range,
were based on high-permittivity ceramics and delivered low loss small cell base station antenna for standalone and
good performance for narrowband, single frequency ap- MIMO 5G, fixed wireless access (FWA) and connected ve-
plications, these new boosters can deliver full mobile per- hicle applications (see Figure 11).9 These devices can also
formance within a broad range of frequency bands (e.g., be stacked to form and steer beams in two dimensions (az-
698 to 2690 MHz) with a single device. The integration re- imuth and elevation) or to form multiple beams and MIMO
quires a matching circuit that allows the device to operate applications.
at the desired bands of interest. Based on conventional low- They also announced their mmWave PSiAn for use in
cost materials and assembly processes, the boosters can be smartphones and other consumer electronics, delivering
made in high volume at very low cost. high throughput with low latency and utilizing directional
Anexampleboosteris5mm3 insizeandoperatesfrom824to beams that generate less interference and maximize ener-
960 MHz and 1710 to 2170 MHz simultaneously. With a gy efficiency.10 The introduction of mmWave connectivity
matching network on the PCB, a VSWR ≤ 3:1 across the for smartphones and other mobile devices faces significant
operating bands and an average total efficiency of 56.7 problems as the signals are easily blocked by fingers, hands,
and 75.8 percent in the 824 to 960 MHz and 1710 to 2170 heads and bodies. When used in combination with distrib-
MHz frequency regions, respectively, is achieved (see Fig- uted radiating elements, PSiDs can be used as a switch and
ure 10).8 beam former to utilize only elements that are able to re-
ceive and transmit line-of-sight or reflected signals resolv-
OTHER UNIQUE TECHNOLOGIES ing this issue. Plasma Antennas recently modeled plasma
Plasma Antennas (PSiAn) offers a range of innovative silicon corner antennas as replacements for array modules
plasma-silicon devices (PSiD) to form the compact RF core for device manufacturers and silicon suppliers. This ap-
of future smart antennas. The PSiDs provide fast, electronic proach closely represented the publicly available solutions
beamforming and beam selection functions. A PSiD can be from Qualcomm and Samsung, for which there are many
regarded as a multi-port, wideband switch that replaces RF handling scenarios that would block the antennas. The ar-
switches, phase shifters and attenuators with one compact, ray Plasma Antennas proposes now solves these problems
and brings the intrinsic qualities of plasma silicon.
Gapwaves AB was founded in 2011 by Professor Per-Si-
Layer 1 mon Kildal at Chalmers University of Technology in Gothen-
burg, Sweden, with the aim of enabling efficient wireless com-
Layer 2 munication through the patented GAP waveguide technolo-
gy. GAP waveguides provide a unique packaging technology
Digital
21
Antenna Design Methodology for
Smartwatch Applications
Phil Lindsey
ARSI LLC, Atlanta, Kan.
C. J. Reddy
Altair Engineering Inc., Hampton, Va.
I
n the early 1990s, Mark Weiser of Xerox the ability to keep time at the fingertips of the
predicted that computers would find their common person, instead of the elite, had its
way into every part of our daily lives by in- disadvantages. If the hands of the user were al-
tegrating seamlessly and unobtrusively—a ready full, the manipulation of a pocket watch
concept he termed ubiquitous computing. “The was just too much hassle —thus, the invention
best user interface,” Weiser observed, “is the of the wristwatch and its widespread acceptance
self-effacing one, the one that you don’t even among British soldiers during World War I.4 The
notice.” He predicted the advent of a wireless wristwatch quickly became among the most
network of connected devices, making infor- common wearable devices in the world, making
mation accessible at any time and in any place. it a prime candidate for enhancement with com-
According to Weiser,1 “In the long run, the per- puter power. Calculator watches first appeared
sonal computer and the workstation will become in 1975. They were followed by a wrist PC in the
practically obsolete because computing access 1980s and a watch with a built-in arcade game.3
will be everywhere: in the walls, on your wrist Later smartwatches have only increased their
and in ‘scrap computers’ (like scrap paper) lying capabilities. 2000 saw what is believed to be
about to be used as needed.” the first collaboration between a clothing com-
The technological world transforms daily into pany and a digital technology company, when
the likeness of Weiser’s vision. Smart devices, Nike and Apple joined to create a fitness tracker
particularly those that are wearable, like smart- embedded in a shoe and designed to work with
watches, have touched and enhanced all aspects an iPod. This Nike+ tool was developed to help
of our lives, from the way we conduct business to runners track time, distance, pace and calories
the way we relax at the end of the day. The par- burned. Eight years later came the Fitbit Classic.
ticular advantage of wearable technology comes Fitness trackers have flourished, more or less,
to the forefront in health and fitness. Wearable since.3 According to mobile communications
devices can monitor heart rate, skin tempera- analysts, the wearables market could be worth
ture, distance traveled, even food intake and $34.2 billion by 2020. Shipments of fitness track-
sleep patterns. Currently, most fitness trackers ers are expected to reach over 60 million units
are mounted on wristbands like watches; a few in the next year or so, while smartwatches are
even include watch functions.2 forecast to exceed 30 million units.3 Computing
The pocket watch was invented in 1762.3 Al- access is indeed everywhere.
though this was a significant revolution, placing
WWW.MWJOURNAL.COM/ARTICLES/27784
22
CHIP ANTENNAS This methodology provides a valid starting point that
Ubiquitous computing makes good antenna design es- eliminates a plurality of unknowns. By following the pro-
sential. Smart device antennas must be small and flexible cedure, installation concerns can be addressed with con-
to fit in small, predefined environments. Some research fidence.
suggests that the bulkiness of smartwatches has tempered For this article, we used a commercially available electro-
their popularity.5 To be useful, these devices need to op- magnetic simulation tool, FEKO12 and its various full wave
erate reliably for a long time without the user needing to solvers, to model the antenna, including the packaging and
modify his or her activity to accommodate the device. This enclosure of the smart device. The finite element method
means that the antenna must respond to movement and (FEM) solver is a perfect tool for complex multi-dielectric
be immune to the near field effects of the human body. volumes in close proximity to an antenna. By using the FEM
The battery life of the device must also be sufficiently long solver, the ground plane can be modified to fit the smart
to satisfy the user. This is largely a function of good anten- device package and verified to operate properly. Extend-
na design, as most of the energy a smart device uses is ing the simulation to include a phantom model will show
consumed during RF transmission. Finally, the completed power absorption, radiation pattern distortion and antenna
device must meet user expectations for price and the FCC’s detuning problems that need to be addressed. Given the
requirements for safety.6 computational complexity of adding an entire phantom, we
One solution to these design challenges is the chip an- used the source decomposition method in FEKO to repre-
tenna. A chip antenna is small and efficient enough to be sent the FEM region of a device as a near field source, then
integrated neatly into a compact smart device, and it is applied the decomposed source to the full phantom model
easy to tune.7 Compared to other options, chip antennas using either the method of moments (MOM) or multi-level
are relatively inexpensive, yet effective. These chips are typ- fast multipole method (MLFMM).
ically based on helix, meander or patch antenna designs.8
Because of their cost effectiveness, small size and mechani- CHIP ANTENNA MODELING
cal viability, analysts forecast the global market for the chip For the smartwatch design, we chose a Fractus Slim
antenna to grow at a 10 percent compound annual growth Reach Xtend chip antenna (FR05-S1-N-0-104). This chip
rate (CAGR) from 2016 to 2020. As more devices trend to has been engineered for wireless applications operating in
wireless connectivity, the boom in smart devices is spurring the 2.4 GHz Bluetooth band. The Slim Reach Xtend has the
competition between the various chip vendors, including advantages of being
Vishay Intertechnology, Antenova Ltd., Johanson Technolo- small, cost effective
gy, Mitsubishi Materials and Fractus.9 and relatively easy to
As with all product developments, designing with chip design with, avoiding
antennas presents challenges that must be accounted for the need to test mul-
in the initial circuit design. Recall that we are dealing with tiple antennas with
small devices. This presents a difficulty because the smaller different resonant
the antenna, the harder it is to achieve good impedance frequencies.13 The
matching and a large bandwidth.10 Therefore, performance Slim Reach Xtend
is highly dependent on the placement and size of the an- datasheet shows the
tenna.7 Second, datasheets reflect the chip on a board, and configuration used
any variation in the ground plane will change the antenna to determine the (a)
pattern and impedance. The overall performance of any performance in the
chip antenna is always dependent on the whole system; it specifications. By
must be compatible with the size and layout of the board, integrating the chip
the complexity of the circuit and the type of enclosure.8 antenna with the
Also, it must not negatively affect any sensors in the de- evaluation board,
vice.7 Finally, on a person, the highly variable dielectric which can be pur-
constant of different body tissues causes the blockage and chased (EB_FR05-
impedance to change.11 Human tissue is extremely lossy, S1-N-0-104), the
so electromagnetic energy from an antenna on the body measured perfor-
will not propagate through the body and radiate into space mance can be com-
as intended, but will largely be absorbed.10 The results are pared to the mod- (b)
bulk power absorption, radiation pattern distortion and an- eled simulation,
tenna detuning.11 Losses can block coverage to other de- providing a verified
vices or reduce the range of the antenna. model to be used in
To address these design challenges, a systematic design any smart device de-
approach has been developed: sign.
• Choose a chip antenna with a demo board From a close-up of
• Model the chip antenna without the board the Fractus chip, the
• Model the chip antenna with the board traces on the chip
(c)
• Measure the chip antenna on the board and the geometry of
• Validate the model with the measured data the evaluation board s Fig. 1 Fractus chip antenna photo
• Model the chip antenna in the smart device were scaled using a (a) and FEM model of the chip (b) and
evaluation board (c). Courtesy: VStar
• Model the device with a human phantom. caliper and entered Systems Inc.14
23
into the FEKO 3D Modeler, CADFEKO. With
this information, an FEM model of the Fractus 2.0 4.0
chip on the evaluation board was created. Fig- 0 0
175 MHz were run around the high accuracy. This results in a valid model that can be
–9
–12
161 MHz FEM model of the used to design future applications with high confidence
–16
–15.2 dB @ –17 dB @ watch to create an in achieving satisfactory real world results. ■
2.36 GHz 2.61 GHz equivalent source to
–18
2.0 2.2 2.4 2.6 2.8 3.0 use with the phan- References
1. Mark Weiser, “Ubiquitous Computing,” Computer, Issue 26, No. 10 (1993), pp.
Frequency (GHz) tom model. Then 71–72.
(a) the MLFMM solver 2. Robin Wright and Latrina Keith, “Wearable Technology: If the Tech Fits, Wear
in FEKO was used It,” Journal of Electronic Resources in Medical Libraries, 11:4 2014, pp. 204–
216.
0.7 1 1.4 to solve the phan- 3. Lindsey M. Baumann, “The Story of Wearable Technology: A Framing Analy-
0.5 2 tom. This process sis,” MA Thesis, Virginia Polytechnic Institute and State University, Blacksburg,
0.4 greatly reduced the Va., 2016.
0.3 3
4. Thad Starner and Tom Martin, “Wearable Computing: The New Dress Code,”
0.2 5 resource and time Computer, Issue No. 06 June 2015 (Vol. 48), pp. 12–15.
0.1 10 requirements with- 5. Kent Lyons, “What Can a Dumb Watch Teach a Smartwatch? Informing the
out compromising Design of Smartwatches,” Proceedings of the 2015 ACM International Sympo-
sium on Wearable Computers, pp. 3–10, 2015.
0.1
10
1.4
5
0.4
0.7
1
0.3
0.5
3
0.2
accuracy.
2
CONCLUSION
Designing antennas for wearable smart devices pres-
ents a unique set of challenges, i.e., dealing with small
environments and lossy human tissue. While the chip an-
tenna offers the efficiency necessary to offset some of
these problems, concerns must be addressed during the
initial circuit design. Placement, compatibility with the
whole system and reliability on a human must be taken
0
330 5 30
0
–5
300 –10 60
5.0 5.0
0 –15
0 –20
Total Gain (dBi)
Total Gain (dBi)
s Fig. 7 Simulated 3D antenna pattern using the full human phantom model, with the smartwatch on the right wrist. Top (a) and
side (b) views and far field antenna gain with ϴ = 90° (c) at 2.45 GHz.
25
Enabling the Smart Home
of the Future
Qorvo’s Wi-Fi solutions offer the highest RF efficiency while
delivering reliable coverage in the smallest form factor.
Qorvo Wi-Fi solutions feature the latest BAW filters & iFEMs and offer the highest
RF efficiency while delivering reliable coverage in the smallest form factor.
Our solutions simplify the smart home, with Wi-Fi everywhere, and resolves
Wi-Fi/LTE coexistence challenges. To learn more visit www.qorvo.com/cpe.
© Qorvo, Inc. | 2018. QORVO is a registered trademark of Qorvo, Inc. in the U.S. and in other countries. www.rfmw.com
Distributed Wi-Fi: How a Pod in Every
Room Enables Connected Smart Homes
Distributed Wi-Fi: How a Pod in Every Room Enables Connected
Smart Homes
This article first appeared on the Qorvo Blog.
Although earlier versions of the Wi-Fi standard provided increased data rates, other challenges remained,
including reliable range and avoiding interference. The Wi-Fi industry used multiple technologies, such as
repeaters or power line extenders, to try to overcome these issues, but it appeared we couldn’t have it
all — reliable range, high data rate and no interference. The capacity continued to be constrained.
https://www.qorvo.com/design-hub/blog/distributed-wifi-how-a-pod-in-every-room-enables-connected-smart-homes 1
© 2018, Qorvo Inc.
27
Keep data rates and data hierarchy in balance
Today’s Wi-Fi connectivity is bottlenecked by the speed of the data connection to the home. Namely, the
speed of data coming into the house is much lower than the transmissions possible in between smart
devices and access points. Wi-Fi speeds can be in gigabits per second, but if the connection to the home is
way less than that, what good does it do?
Even if you have 7 Gb/s between devices, the home access is only working at 100 Mb/s. The hierarchy is
out of balance, as shown in the following figure.
Fortunately, Wi-Fi continues to move ahead. While carriers are racing to increase the data rates with
FTTH, DOCSIS 3.1 and even LTE/5G gateways, IEEE 802.11ax will increase actual data throughput, focusing
on higher capacity in the home. In addition, robust technologies to reduce interference are enabling
multiple radio systems in the smart home.
So, with next-generation technology and IEEE 802.11ax, we expect to see improvements to wireless indoor
architecture and long-term upgrades to infrastructure, to meet customer demand. As a result, a shake-up of
data rates and a re-establishment of the data hierarchy should create data connections that make more
sense.
https://www.qorvo.com/design-hub/blog/distributed-wifi-how-a-pod-in-every-room-enables-connected-smart-homes 2
© 2018, Qorvo Inc.
28
service rely on sensors to track data, sometimes collected to a cloud to analyze it, and notify users when
things are not normal within their environment. Today’s homes can have 10 Wi-Fi devices, but smart home
sensors could reasonably increase this number to 50-100.
To achieve a truly connected smart home, an enhanced “pod in every room” design serves as the best
approach to achieve this distributed Wi-Fi architecture with IoT communications. Because every pod
serves as a wireless access point, every access point will support Wi-Fi and IoT standards. This includes the
home’s increased Wi-Fi requirements as well as Zigbee and Bluetooth devices. These devices could even be
controlled via audio/voice assistance on command.
https://www.qorvo.com/design-hub/blog/distributed-wifi-how-a-pod-in-every-room-enables-connected-smart-homes 3
© 2018, Qorvo Inc.
29
With IEEE 802.11ax, all devices would talk to the wireless router on multiple channels. This design
eliminates the need for extra gateways or multiple Ethernet/cable/fiber connections installed within the
home to link a mesh system.
In addition, with a pod in every room, there is no need for meshing Zigbee and Bluetooth anymore, and that
makes a big difference. No meshing means longer battery life for the devices, simple setup and
troubleshooting processes, and lower costs for the user. This enhanced quality of service (QoS) would also
help reduce service calls and in-person technician visits for the provider.
Ultimately, the pods would offer more channels and connect IoT devices smoothly and easily. And the
increased connectivity would propagate the IoT with sensors, devices and audio assistance, creating a
smart home.
Strengthen the IoT with distributed Wi-Fi that includes all wireless technology
options
Distributed Wi-Fi will support high- and low-speed devices in every room. As modern home network
access systems download and buffer content through the connection to the house, installing distributed Wi-
Fi with high-capacity capabilities can move that content through the house faster, with better quality,
making multiple users happier.
But at the end of the day, the value is not in the specific technology used — as wireless communications
will be easier with all relevant technologies embedded in a single pod. The value, however, will be in
addressing consumer demand for more seamless connectivity, with support for all technologies, and
ensuring IoT devices contribute to a truly smart home environment.
https://www.qorvo.com/design-hub/blog/distributed-wifi-how-a-pod-in-every-room-enables-connected-smart-homes 4
© 2018, Qorvo Inc.
30
Want to learn more about distributed Wi-Fi? Listen to our recorded webinar for more details, including
standards, security, privacy and legislation.
https://www.qorvo.com/design-hub/blog/distributed-wifi-how-a-pod-in-every-room-enables-connected-smart-homes 5
© 2018, Qorvo Inc.
https://www.qorvo.com/design-hub/blog/distributed-wifi-how-a-pod-in-every-room-enables-connected-smart-homes 5
© 2018, Qorvo Inc.
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