KR100727133B1 - Noise and interference margin extensible cdma modulator in the mobile communication terminal - Google Patents

Abstract

A CDMA modulation device extending a noise and an interference margin in a mobile communication terminal is provided to make it possible to extend the noise and the interference margin according as a convolution encoder with half rate as compared with a conventional device is used and the number of bits for correcting an error at each data bit are increased, accordingly to increase the number of terminal users located at an area managed by the same base station or to enhance the noise and the interference margin even in boundary points of a cell or an environment where a noise and a fading phenomenon are severe, and as a result to enhance quality of a voice call connection or throughput of a data communication. A CDMA modulation device extending a noise and an interference margin in a mobile communication terminal comprises a serial/parallel converter(20), a convolution encoder(21), a symbol repeater(22), a block interleaver(23) and baseband filters(29-1,29-2). The serial/parallel converter performs a CDMA modulation process individually for I-channel component data and Q-channel component data into which inputted data is divided. The convolution encoder convolutes the I-channel component data and the Q-channel component data, outputted by the serial/parallel converter, by each data symbol and outputs each convoluted data to a corresponding data line. The symbol repeater repeatedly outputs an I-channel component symbol and a Q-channel component symbol to each corresponding data line at a constant speed according to a transmission speed. The block interleaver interleaves the I-channel component symbol and the Q-channel component symbol into each block and outputs the each block to a corresponding data line. The baseband filters(29-1,29-2) filter the I-channel component data and the Q-channel component data, outputted by the clock interleaver, into a corresponding data line.

Description

[0001] The present invention relates to a Noise and Interference Margin Extensible CDMA Modulator In The Mobile Communication Terminal,

1 is a diagram illustrating a configuration of a CDMA modulation terminal for a paging channel and a traffic channel of a conventional mobile communication terminal.

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a mobile communication terminal,

Description of the Related Art [0002]

20: serial / parallel converter 21: convolutional encoder

22: symbol repeater 23: block interleaver

24: long code generator 25: decimator

26-1, 26-2, 27-1, 27-2, 28-1, 28-2: coupler

29-1, 29-2: Baseband filter

The present invention relates to a CDMA modulation apparatus for a mobile communication terminal, and more particularly to a CDMA modulation apparatus for a mobile communication terminal, which divides data input to a CDMA modulation terminal into an I-channel and a Q- To improve the noise and the interference margin. The present invention also relates to a CDMA modulation apparatus that extends noise and interference margins in a mobile communication terminal.

In general, the CDMA communication scheme has the advantage that it can use the same frequency as the increase of the call capacity in a large number of cells (base stations) and less interference than other schemes.

When a mobile communication terminal employing the CDMA communication method uses signals overlapping in time and frequency axes, when the number of connected users increases in a certain base station or when communication is performed at a high power at a boundary point of a base station, In particular, the signal demodulation of the terminal is degraded in an environment where noise or fading is severe. As a result, the voice quality of the terminal is deteriorated, The throughput is reduced.

Meanwhile, as shown in FIG. 1, the configuration of a CDMA modulation terminal for a paging channel and a traffic channel of a conventional mobile communication terminal includes a convolutional encoder for error correction A Symbol Repetition 12 for the same Symbol Rate, a Block Interleaver 13 for preventing Burst Noise, and a Block Interleaver 13 for preventing burst noise, A decimator 15 and a baseband filter 19-1 for multiplexing long codes and a long code generator 14 for the identity of a long code, 19-2).

The operation of the CDMA modulation stage will now be described. The data coming from the base station to the paging channel (or traffic channel) now has four types: 9.6 / 4.8kbps or 2.4 / 1.2kbps, (For example, 'K' (constant) for a convolutional encoder having a rate of 1/2) with a data symbol of 19.2 / 9.6 ksps (ksymbol / second) (4.8 / 2.4 ksps) length 'is input to the symbol repeater 12, and the symbol repeater 12 repeatedly outputs the input data symbols at a rate of 19.2 ksps according to the transmission rate thereof .

The data symbols output by the symbol repeater 12 are input to the block interleaver 13 and the block interleaver 13 blocks the data symbols in order to prevent burst noise in the radio (Ober-The-Air) The long code generator 14 generates a long code for data scrambling and transmits it to the decimator 15 at a rate of 1.2288 Mcps. The decimator 15 multiplexes the long code, And outputs the scrambled data symbol at a rate of 19.2 ksps.

Thereafter, the interleaved data symbols output by the block interleaver 13 are scrambled while being combined by the combiner 16 with the scrambled data symbols output through the decimator 15, and the scrambled data symbols are subjected to channel classification (pilot / (In-Phase Channel) and Q-channel (Quadrature-Channel) components after being spread by the Walsh function n of the combiner 17 for the synchronization / paging / traffic channel Spread by the PN code combiner 18-1 and 18-2 and then transmitted through the baseband filters 19-1 and 19-2 and multiplexed on the carrier wave.

As described above, in the conventional mobile communication terminal, in performing the CDMA modulation, the convolutional encoder 11 having a rate of '1/2' (when 1 bit of actual data is subjected to convolutional coding, 1 bit is added and two bits are output), convolutional coding is performed in which one bit is added to each bit for error correction, and various processes are performed on the coded data symbol, and then I - channel and Q-channel, respectively, the number of terminal users located in the management area (i.e., cell) of the same base station increases due to the lack of error correction bits, or the cell boundary point or noise or fading is severe There is a problem that noise and interference margins are small and the terminal performance is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems and it is an object of the present invention to provide a method and apparatus for performing a series of data modulation processes in a CDMA modulation terminal for a paging channel or a traffic channel of a mobile communication terminal, To divide the input data into data having the I-channel component and the Q-channel component before performing the modulation processing, thereby using the convolutional encoder having a half rate as compared with the conventional one , Thereby expanding the number of error correction bits to be added for each data bit in the convolutional coding, thereby extending the noise and interference margin.

According to an aspect of the present invention, there is provided a CDMA modulator for performing a series of CDMA modulation on data input through a paging channel or a traffic channel in a mobile communication terminal, A serial / parallel converter is added to the input side for dividing input data into data having an I-channel component and a Q-channel component; The S / and the S / P converter for performing CDMA modulation processing with respect to each of the I- and Q- channel component data channel component data divided by the deserializer, I- channel component data outputted from the S / P converter Channel component data and Q-channel component data symbols output from the convolutional encoder; and a convolutional encoder for convoluting the Q-channel component data and the Q-channel component data into data symbols, Channel component data symbols and Q-channel component data symbols output from the symbol repeater are interleaved into blocks, respectively, and the I-channel component data symbols and the Q-channel component data symbols output from the symbol repeater are interleaved To a data line corresponding to the block interleaver, And a baseband filter for filtering the data of the I-channel and the Q-channel, respectively, corresponding to the data lines.

The CDMA modulator that extends noise and interference margins in the mobile communication terminal may further include a scrambler for scrambling the interleaved data symbols outputted through the I-channel data line and the Q-channel data line by the block interleaver, A scramble combiner for combining a scrambled data symbol for multiplexing and outputting a long code generated by a long code generator in a decimator, a combiner for scrambling I-channel component data scrambled by the scrambling combiner, And a combiner for Walsh spreading for function spreading is implemented on the I-channel data line and the Q-channel data line, respectively.

Another aspect of the present invention is summarized as a mobile communication terminal including a long code generator for generating a long code for CDMA modulation in a mobile communication terminal, a decimator for multiplexing a long code, and a transmitter for spreading data of the I- And a base band filter for filtering data of I-channel and Q-channel spread by the PN code spreading combiner, respectively, the CDMA modulation apparatus comprising: A serial-to-parallel converter for dividing input data into data having an I-channel component and a Q-channel component, and outputting the divided data to respective data lines; A convolutional encoder for performing convolutional coding of the I-channel component data and the Q-channel component data output from the S / P converter into data symbols and outputting the resultant data to corresponding data lines; A symbol repeater for repeatedly outputting I-channel component data symbols and Q-channel component data symbols output from the convolutional encoder according to a transmission rate and outputting the I-channel component data symbols and the Q-channel component data symbols to corresponding data lines at a constant rate; A block interleaver interleaving the I-channel component data symbols and the Q-channel component data symbols output from the symbol repeater into blocks and outputting the interleaved blocks to corresponding data lines; A scramble combiner for combining interleaved I-channel component data symbols and Q-channel component data symbols output from the block interleaver with scrambled data symbols output from the decimator; And a Walsh spreading combiner for performing Walsh function spreading on I-channel component data and Q-channel component data scrambled by the scrambling combiner, respectively, and then transmitting the Walsh function spread to a corresponding PN code spreading combiner And to implement a CDMA modulation apparatus that extends noise and interference margins.

The convolutional encoder is characterized in that the rate is 1/4.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the present invention, in implementing the CDMA modulation stage of the mobile communication terminal, a serial-to-parallel converter is added to the data input side for CDMA modulation of a paging channel or a traffic channel, By dividing the input data into the I-channel component and the Q-channel component by connecting with the data line and the Q-channel data line, a convolutional encoder having a rate of '1/4' As a result, the noise and the interference margin are enlarged to prevent the deterioration of the terminal performance. The structure of the CDMA modulation stage is shown in FIG. 2 attached hereto.

That is, as shown in FIG. 2, the configuration of the CDMA modulation stage in which the noise and interference margin is extended in the mobile communication terminal according to the present invention includes a serial-to-parallel converter 10 configured on the data input side of the CDMA modulation stage, A symbol interleaver 23, a long code generator 24, a decimator 25, and baseband filters 29-1 and 29-2, as well as a convolutional encoder 21, a symbol repeater 22, a block interleaver 23, As compared to the conventional CDMA modulation stage shown in Fig. 1, a serial-to-parallel converter 20 has been added and conventionally scrambled data symbols are spread by Walsh functions and then converted into I- and Q- being copied, respectively, after which the components other words, the combiner for the PN spreading code (18-1, 18-2) and the base band filters (19-1, 19-2) and a cosine wave (cos2πf _c t) or a sine wave (sin2πf _c t) the I- and Q- channel data line channel multiplier like for transition to the RF frequency band by multiplying the data The input data is divided into the I-channel component and the Q-channel component by the serial-to-parallel converter 20 in the present invention, Components such as the parallel converter 20 and the convolutional encoder 21, the symbol repeater 22 and the block interleaver 23 are connected to the I-channel data line and the Q-channel data line, respectively.

Since the data symbols are divided into I-channel and Q-channel by the convolutional encoder 21, the symbol repeater 22 and the block interleaver 23, the interleaved data outputted by the block interleaver 23 Combiners 26-1 and 26-2 for combining the symbols with the scrambled data symbols output through the decimator 25 are implemented in the I-channel data line and the Q-channel data line, respectively, and the Walsh function The combiners 28-1 and 28-2 are also implemented on the I-channel data line and the Q-channel data line, respectively.

Since the input data is divided into the I-channel component and the Q-channel component by the serial-to-parallel converter 20 and the interval per bit of the input data is doubled, the rate becomes '1' / 4 'is used as a convolutional encoder.

At this time, the components such as the symbol repeater 22, the block interleaver 23, the long code generator 24, the decimator 25, and the baseband filters 29-1 and 29-2 may be replaced with conventional components In comparison, the basic functions are the same, except that they are divided and processed into I-channel and Q-channel.

The operation of the CDMA modulation stage based on the above-described configuration will now be described.

First, when data is input from the base station through the paging channel (or the traffic channel) at a rate of 9.6 / 4.8 kbps (2.4 / 1.2 kbps) to the CDMA modulation terminal, the serial / parallel converter 20 converts the input data into I- And Q-channel components, respectively, and outputs them to the I-channel data line and the Q-channel data line, respectively. That is, the serial-to-parallel converter 20 splits the input data into I-channel component data and Q-channel component data in parallel and outputs the data at a rate of 4.8 / 2.4 kbps (1.2 / 1.6 kbps) .

In this way, data output through the I-channel data line and the Q-channel data line, respectively, is input to the convolutional encoder 21, where the interval per bit of the data input to the CDMA modulation stage is 'T' Assuming that the interval per bit of each channel component data input to the convolutional encoder 21 through the serial-to-parallel converter 20 is extended by '2T', that is, twice, the convolutional encoder 21 And is implemented as a convolutional encoder 21 having a rate of '1/4' under the same condition as the prior art.

Each channel component data input to the convolutional encoder 21 through the I-channel data line and the Q-channel data line is 19.2 / 9.6 ksps (4.8 / 2.4 ksps) by the corresponding convolutional encoder 21, And is inputted to the symbol repeater 22 through the corresponding data lines, that is, the I-channel data line and the Q-channel data line. At this time, the convolutional encoder 21 performs the convolutional encoding Since the rate R is '1/4', convolutional coding is performed in which 3 bits are added to each bit for error correction, thereby expanding the noise and interference margin.

Then, the symbol repeater 22 repeatedly repeats I-channel component data symbols and Q-channel component data symbols input through each channel data line according to their transmission rates, Data line.

At this time, each channel component data symbol outputted through the I-channel data line and the Q-channel data line by the symbol repeater 22 is input to the block interleaver 23, and the block interleaver 23 receives the over- In order to prevent burst noise in the " The-Air " period, the data symbols input through the respective channel data lines are interleaved into blocks and output to corresponding channel data lines.

The interleaved data symbols output by the block interleaver 23 through the I-channel data line and the Q-channel data line respectively are multiplexed by the long code generator 24 and decimated by the decimator 25, And the scrambled data symbols are combined by the combiners 26-1 and 26-2 and the scrambled data symbols output from the Walsh function (PN-Sequence) combiners 28-1 and 28-2 after being spread by the respective combiners 27-1 and 27-2 that perform the PN codes Are multiplexed and transmitted on the carrier wave after passing through the baseband filters 29-1 and 29-2, respectively.

The embodiments according to the present invention are not limited to those described above, and various alternatives, modifications, and alterations can be made within the scope of the present invention to those skilled in the art.

As described above, according to the present invention, in performing a series of data modulation processes at a CDMA modulation terminal for a paging channel or a traffic channel of a mobile communication terminal, a serial / parallel converter is added to a data input side, Channel component, and then performs modulation processing. By using a convolutional encoder having a half rate as compared with the prior art, the number of bits for error correction increases for each data bit The noise and interference margin can be expanded. Accordingly, it is possible to improve the noise and interference margin even in an environment where the number of terminals located in the management area of the same base station increases, or the boundary points of cells or noise or fading are severe, The call quality of the voice call and the throughput during data communication are improved. It can be improved.

Claims (4)

A CDMA modulation apparatus for performing a series of CDMA modulation processing on data input through a paging channel or a traffic channel in a mobile communication terminal, A serial / parallel converter is added to the input side of the CDMA modulation apparatus for dividing input data into data having an I-channel component and a Q-channel component; The S / and the S / P converter for performing CDMA modulation processing with respect to each of the I- and Q- channel component data channel component data divided by the deserializer, I- channel component data outputted from the S / P converter Channel component data and Q-channel component data symbols output from the convolutional encoder; and a convolutional encoder for convoluting the Q-channel component data and the Q-channel component data into data symbols, Channel component data symbols and Q-channel component data symbols output from the symbol repeater are interleaved into blocks, respectively, and the I-channel component data symbols and the Q-channel component data symbols output from the symbol repeater are interleaved To a data line corresponding to the block interleaver, And a baseband filter for filtering the data of the I-channel and the Q-channel by the data lines corresponding to the I and Q channels, respectively, in the mobile communication terminal. The method according to claim 1, For scrambling the interleaved data symbols outputted through the I-channel data line and the Q-channel data line by the block interleaver, a scramble data symbol for multiplexing and outputting the long code generated by the long code generator in the decimator, Channel component data scrambled by the scrambling combiner and a combiner for Walsh diffusion for spreading the Walsh function of the Q-channel component data is provided to the I-channel data line and the Q- Line in the mobile communication terminal, and the noise and interference margin are extended in the mobile communication terminal. A long code generator for generating a long code for CDMA modulation in the mobile communication terminal, a decimator for multiplexing long codes, a combiner for spreading data of I-channel and Q-channel respectively into PN code, A CDMA modulator comprising a baseband filter for respectively filtering data of I-channel and Q-channel spread by a spreading combiner, A serial-to-parallel converter provided on a data input side for CDMA modulation, for dividing input data into data having an I-channel component and a Q-channel component and outputting the divided data to respective data lines; A convolutional encoder for performing convolutional coding of the I-channel component data and the Q-channel component data output from the S / P converter into data symbols and outputting the resultant data to corresponding data lines; A symbol repeater for repeatedly outputting I-channel component data symbols and Q-channel component data symbols output from the convolutional encoder according to a transmission rate and outputting the I-channel component data symbols and the Q-channel component data symbols to corresponding data lines at a constant rate; A block interleaver interleaving the I-channel component data symbols and the Q-channel component data symbols output from the symbol repeater into blocks and outputting the interleaved blocks to corresponding data lines; A scramble combiner for combining interleaved I-channel component data symbols and Q-channel component data symbols output from the block interleaver with scrambled data symbols output from the decimator; And a Walsh spreading coupler for performing Walsh function spreading on the I-channel component data and Q-channel component data scrambled by the scramble combiner, respectively, and then transmitting the Walsh function spreading to a corresponding PN code spreading combiner A CDMA modulation device that extends noise and interference margins in a mobile communication terminal. 3. The method according to claim 1 or 3, Wherein the convolutional encoder has a rate of 1/4, and the noise and interference margin is extended in the mobile communication terminal.

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