KR20020041568A - Apparatus and controlling method for high rate data transmitter in mobile communication system - Google Patents

Abstract

PURPOSE: A high speed data transmitter in a mobile communication system and a control method thereof are provided to reduce a deterioration of a transmission rate by reducing amount of additional data. CONSTITUTION: A user data output section(100) outputs frame data. A cyclic redundancy code insertion section(102) receives the frame data and verifies a frame. A first frame identification number generator(104) outputs an identification number of the frame. A tail bit insertion section(106) inserts the identification number of the frame and the tail bit. A convolution coder(108) encodes the frame data from the tail bit insertion section(106). A second frame identification number generator(104) is synchronized with the first frame identification number generator(104) and outputs an identification number of the frame. A Viterbi decoder(112) decodes the identification number of the frame and the data from the convolution coder(108) by frames. A tail bit removing section(114) removes a tail bit included in the decoded frame from the Viterbi decoder(112). A CRC tester(116) tests whether an error is generated in the frame data from the tail bit removing section(114).

Description

Apparatus and controlling method for high rate data transmitter in mobile communication system

The present invention relates to a mobile communication system, and more particularly, high-speed data in a mobile communication system using a convolutional encoder and an ARQ (Automatic Repeat Request) technique to enable reliable high-speed data transmission without a decrease in transmission rate. The present invention relates to a transmission apparatus and a control method thereof.

Recently, with the rapid progress of multimedia, the interest in high-speed data transmission such as voice, internet and moving picture is rapidly increasing through mobile communication media, and IMT-2000 system that enables high-speed data transmission up to 2Mbps reflecting this trend. Put commercialization in sight

The IMT-2000 system, which is the next generation mobile communication system, is a system that integrates various mobile communication networks and services formed to provide various kinds of existing services into one to provide all possible mobile communication services.

In addition, the IMT-2000 system is intended to provide a comprehensive mobile communication service to subscribers by having the capability to cope with multi-services and multi-environments using various types of wireless access and a large capacity of subscribers.

In other words, it is a system to provide multimedia communication and international roaming services such as data and video with voice and transmission speeds up to 2Mbps, and to implement a wired / wireless integrated system based on ATM network.

In particular, the IMT-2000 system simultaneously uses an ARQ (Automatic Repeat Request) technique together with an error correction encoder that uses an additional error correction code for overcoming a poor channel environment and for reliable data transmission.

However, the IMT-2000 system has a problem in that the rate reduction of the system increases because additional data is added in duplicate for error recovery.

In addition, the IMT-2000 system has a problem of deteriorating a wireless environment when many users transmit data in a dense environment.

Accordingly, an object of the present invention is to provide a tail bit used for a sequential error correction encoder, which is a convolutional encoder, to solve the function of the identification number of a frame required by the ARQ technique. The present invention also provides a high-speed data transmission apparatus and a control method thereof in a mobile communication system that can reduce a decrease in transmission rate by reducing the amount of additional data.

A feature of the high-speed data transmission apparatus in the mobile communication system according to the present invention for achieving the above object is, the user data output unit for outputting the frame data, the frame data output from the user data output unit is applied to verify the frame A cyclic redundancy code (CRC) insertion unit, a first frame identification number generator (FIG) unit for outputting a frame identification number, a recognition number of a frame output from the first FIG unit, and a verified frame output from the CRC insertion unit A tail end inserter for inserting a tail bit, a convolutional encoder for encoding frame data output from the tail bit inserter, and a second FIG synchronized with the first FIG part and outputting a recognition number of the frame A recognition number of the frame output from the second FIG unit and the convolutional encoder Viterbi decoder receiving data and decoding for each frame, Tail bit removing unit for removing the tail bit from the decoded frame output from the Viterbi decoder and outputting the frame from which the tail bit is removed to the second FIG unit, The tail CRC checking unit for checking whether frame data output from the bit removing unit is impossible to recover and an error occurred frame, receiving data unit for receiving a normal frame output from the CRC checking unit as user data, and receiving the data unit from the CRC checking unit to the receiving data unit. It consists of a receiving end consisting of an ARQ (Automatic Repeat Request) unit for requesting an error frame that is not output and retransmits to the user data unit.

In addition, a feature of the control method of the high-speed data transmission apparatus in the mobile communication system according to the present invention for achieving the above object, CRC insertion unit to initialize the first FIG unit and verify the frame output from the user data output unit Adding a frame to the frame; transmitting a frame identification number generated by the first FIG unit to a tail bit inserter to attach a tail bit to each frame, and transmitting the data to the convolutional encoder; and requesting an ARQ to the frame data. Determining whether a signal has been received; re-transmitting ARQ-requested frame data to the user data output unit of the transmitting end if the ARQ request is received; and transmitting data if the ARQ request is not received. It is determined whether a termination signal has been input, and if a data transmission termination signal has been input, Terminating the data transmission; and generating a recognition number of the next frame and sending the identification number to the frame transmission step if the data transmission termination signal is not input.

In addition, the control method of the high-speed data transmission apparatus in the mobile communication system according to the present invention for achieving the above object is, by initializing the second FIG unit and outputs the encoded frame data output from the convolutional encoder to the Viterbi decoder Decoding frame data, removing tail bits from the decoded frame data, and outputting a frame from which tail bits have been removed to a CRC checker to determine whether the frame data is an unrecoverable and error-prone frame; If there is no frame data error signal, it is determined whether the frame data is retransmitted frame data, and if the frame data is retransmitted data, reassembling the frame. If signal is input Terminating the data transmission; determining whether the data transmission termination signal is input if the frame data is not retransmitted as a result of the determination; and terminating the data transmission if the data transmission termination signal is input; If it is not input, generating the identification number of the next frame and sending it to the receiving frame decoding step, and if there is a frame data error signal, and sending the frame retransmission request signal to the receiving frame decoding step.

1 is a block diagram of a high speed data transmission apparatus in a mobile communication system according to the present invention;

2 is a flowchart of a transmitting end of a high speed data transmission apparatus in a mobile communication system according to the present invention;

3 is a flowchart of a receiving end of a high speed data transmission apparatus in a mobile communication system according to the present invention.

<Description of the symbols for the main parts of the drawings>

100: user data output unit, 102: CRC insertion unit,

104: 1st FIG part, 106: tail bit insertion part,

108: convolutional encoder, 110: second FIG unit,

112: Viterbi decoder, 114: tail bit removing unit,

118: reception data unit, 120: ARQ.

Hereinafter, a preferred embodiment of a high speed data transmission apparatus and a control method thereof in a mobile communication system according to the present invention will be described with reference to the accompanying drawings.

1 is a block diagram of a high speed data transmission apparatus in a mobile communication system according to the present invention.

As shown in FIG. 1, a user data output unit 100 for outputting frame data and a cyclic redundancy code (CRC) insertion unit for verifying a frame by receiving the frame data output from the user data output unit 100. (102), a first frame identification number generator (FIG) 104 for outputting a frame identification number, a frame identification number output from the first fig unit 104, and an output from the CRC insertion unit (102). A tail bit inserter 106 for inserting a tail bit for each verified frame, a convolutional encoder 108 for encoding frame data output from the tail bit inserter 106, and the first FIG unit. A second FIG unit 110 which is synchronized with the 104 and outputs a recognition number of the frame, a recognition number of the frame output from the second FIG unit 110 and data output from the convolutional encoder 108 are applied to the frame Poor decryption The tail bit system for removing the tail bit from the decoded frame output from the Viterbi decoder 112 and the Viterbi decoder 112 and outputting the frame from which the tail bit is removed to the second FIG unit 110. CRC check unit 116 that checks whether the frame 114 output from the tail bit removing unit 114 is not recoverable and an error has occurred, and the normal output from the CRC check unit 116. Receive data unit 118 for receiving a frame as user data, and ARQ (Automatic Repeat) for requesting an error frame that is not output from the CRC checker 116 to the receive data unit 118 and retransmitting to the user data unit 100 Request) 120 is configured.

Here, the user data output unit 100, the CRC insertion unit 102, the first FIG unit 104, the tail bit insertion unit 106 and the convolutional encoder 108 is a transmitting end, the second FIG unit 110, beater The non-decoder 112, the tail bit removing unit 114, the CRC checking unit 116, the receiving data unit 118, and the ARQ unit 120 are receivers.

The operation of the high speed data transmission apparatus in the mobile communication system according to the present invention configured as described above is as follows.

First, the user data output unit 100 outputs user data to the CRC inserting unit 102 so that the receiving end can verify the received frame.

The CRC inserter 102 then outputs frame data to the tail bit inserter 106.

On the other hand, the first FIG unit 104 outputs the identification number of the frame to the tail bit insertion unit 106.

In this case, the tail bit insertion unit 106 is attached to the tail bit for each frame.

Thereafter, the tail bit inserting unit 106 outputs data to which the tail bits are attached to each frame to the convolutional encoder 108.

Here, frame data applied to the convolutional encoder 108 is encoded.

In particular, a sequential error correction encoder such as the convolutional encoder 108 is a tail bit for initializing the state of the encoder every frame in order to reduce the delay between the transmitter and receiver and reduce the complexity of hardware when decoding at the receiver. A zero bit is inserted and the length of the inserted tail bit increases in proportion to the length of the constraint length of the sequential error correction encoder.

Meanwhile, the convolutional encoder 108 outputs the encoded frame data to the Viterbi decoder 112 at the receiving end.

The second FIG unit 110 operates in synchronization with the first FIG unit 104 and outputs a frame identification number to the Viterbi decoder 112.

In this case, the Viterbi decoder 112 may track the state corresponding to the inserted tail bit as a starting point when tracking the survival path back each time each frame is received.

Therefore, if the tail bits can be known between the transmitter and the receiver, the decoding can be performed even if not specifically "0". In particular, when the identification number of each frame is inserted as the tail bit, the receiver estimates the identification number of the currently received frame and sets this value as a starting point at which the decoder can track the survival path. If not, the tail bit should be matched between the transmitting and receiving end.

Subsequently, the Viterbi decoder 112 decodes the encoded frame data and outputs the decoded frame data to the tail bit removing unit 114.

Thereafter, the tail bit removing unit 114 removes the tail bit of the frame and outputs the frame from which the tail bit has been removed to the CRC check unit 116.

At this time, the CRC checker 116 checks whether or not a frame is an error that is not recoverable from the frame data.

Subsequently, the CRC checker 116 outputs a normal frame to the reception data unit 118 that receives the normal frame as user data.

In addition, the CRC checker 116 requests an error frame that cannot be outputted to the reception data unit 118 and outputs it to the ARQ unit 120 that retransmits the user data output unit 100.

The detailed operation of the high speed data transmission apparatus in the mobile communication system according to the present invention operated as described above is as follows.

First, when the transmission and reception starts, the first and second FIG units 104 and 110 of the transmission and reception end operate in synchronization with each other. In addition, since the frame identification number generated by the first and second FIG 104 and 110 is used as a tail bit in the transmitting / receiving end, the tail bit used in the encoder of the transmitting end can be known when decoding the data at the receiving end. Decryption is possible.

When the identification number of the frame is generated and inserted, the first FIG 104 of the transmitting end sequentially generates the identification number of the corresponding frame, and the identification number of the generated frame is a tail bit in the convolutional encoder 108. Is inserted. At this time, in order to prevent an error occurring in the tail bit portion, the frame's identification number undergoes an appropriate encoding process within the length of the tail bit used.

Meanwhile, the decoding process of the receiver sets the state of the Viterbi decoder 112 as a tail bit using the identification number of the frame generated by the second FIG 110 synchronized with the transmitter, and then traces the survival path to recover the error. Goes.

At this time, the Viterbi decoder 112 of the receiving end is preferably configured in parallel in consideration of the transmission delay of the frame that may occur in the transmitting / receiving end and the channel. In this case, decoding is performed using a limited number of delayed frame identification numbers as initial states of individual decoders, and a decoded frame is regarded as a transmitted frame.

In addition, the frame in which the non-recoverable error occurs in the Viterbi decoder 112 is determined by the CRC checker 116, and retransmission is required. The received frame is stored in a buffer and retransmitted until the retransmission is completed after the retransmission request. At this point of completion, the frame is recombined based on a tail bit which is a recognition number of a frame.

The operation of the transmitter of the high speed data transmission apparatus in the mobile communication system according to the present invention configured as described above will be described with reference to FIG.

First, the frame is added to the CRC insertion unit 102 so as to initialize the first FIG unit 104 and verify the frame output from the user data output unit 100 (S101).

Subsequently, the frame recognition number generated by the first FIG unit 104 is transmitted to the tail bit insertion unit 106 to attach tail bits for each frame, and the data is transmitted to the convolutional encoder 108 (S103).

In operation S105, it is determined whether a signal for requesting ARQ is received for the frame data.

If the ARQ request is received as a result of the determination in S105, the ARQ request frame data is retransmitted to the user data output unit 100 of the transmitter (S107).

If the ARQ request is not received as a result of the determination in S105, it is determined whether a data transmission termination signal is input (S109). If the data transmission termination signal is input, the data transmission is terminated.

When the data transmission termination signal is not input as a result of the determination in S109, a recognition number of the next frame is generated and sent to the frame S111, which is a transmission step of the frame S111.

The operation of the receiving end of the high speed data transmission apparatus in the mobile communication system according to the present invention configured as described above will be described with reference to FIG.

First, the second FIG unit 110 is initialized, and the encoded frame data output from the convolutional encoder 108 is output to the Viterbi decoder 112 to decode the frame data (S201) (S203).

Subsequently, the tail bit is removed from the decoded frame data and the frame from which the tail bit is removed is output to the CRC checker 116 to determine whether the frame data is impossible to recover from the frame data (S205).

If there is no frame data error signal as a result of the determination in S205, it is determined whether the frame data is retransmitted (S207). If the frame data is retransmitted, the frame is reassembled (S209).

Subsequently, when frame recombination is completed, it is determined whether a data transmission termination signal is input (S211), and when the data transmission termination signal is input, the data transmission is terminated.

If it is determined in S207 that the frame data is not retransmitted, it is determined whether a data transmission termination signal is input (S213). If the data transmission termination signal is input, the data transmission is terminated.

When the data transmission termination signal is not input as a result of the determination in S213, an identification number of the next frame is generated (S215) and sent to S203, which is a reception frame decoding step.

In addition, if there is a frame data error signal as a result of the determination in S205, a frame retransmission request signal S217 is sent to S203, which is a reception frame decoding step.

As described above, the present invention combines the convolutional encoder and the ARQ technique to reduce the degradation of the transmission rate and to provide reliable data transmission, which can be applied to various high-speed communication systems other than the CDMA technology.

Therefore, it is applied to all next-generation high-speed mobile communication systems, thereby enabling reliable high-speed data transmission without further reducing the transmission rate, thereby reducing the subscriber communication cost and reducing the load on the base station.

Claims (3)

A user data output unit for outputting frame data, a cyclic redundancy code (CRC) insertion unit for verifying a frame by receiving the frame data output from the user data output unit, and a first frame identification number generator for outputting a frame identification number A tail bit inserter for inserting a tail bit for each frame identified from the CRC inserter and a recognition number of a frame output from the first FIG unit, and frame data output from the tail bit inserter A transmitting end comprising a convolutional encoder for encoding the code; A second FIG unit which is synchronized with the first FIG unit and outputs a recognition number of the frame, a Viterbi decoder which receives the identification number of the frame output from the second FIG unit and the data output from the convolutional encoder and decodes each frame, A tail bit removing unit for removing tail bits from the decoded frame output from the Viterbi decoder and outputting the frame from which the tail bits have been removed to the second FIG unit, and recovering from the frame data output from the tail bit removing unit is impossible Is a CRC checker for checking whether a frame is generated, a reception data unit for receiving normal frames output from the CRC checker as user data, and an ARQ requesting an error frame that cannot be output from the CRC checker to the reception data unit and retransmitted to the user data unit. To the receiving end consisting of an Automatic Repeat Request High speed data transmission apparatus in a mobile communication system, characterized in that a generated. In the control method of the transmitting end of the transmission apparatus in a mobile communication system, Adding a frame to the CRC insertion unit so as to initialize the first FIG unit and verify the frame output from the user data output unit; Transmitting the frame identification number generated by the first FIG unit to a tail bit inserter to attach tail bits to each frame and transmitting the data to the convolutional encoder; Determining whether a signal for requesting ARQ is received for the frame data; Retransmitting the frame data for which ARQ is requested to the user data output unit of the transmitting end when the ARQ request is received as a result of the determination; Determining whether a data transmission termination signal is input when the ARQ request is not received, and terminating the data transmission when the data transmission termination signal is input; And if the data transmission termination signal is not input, generating the identification number of the next frame and sending the identification number to the frame transmission step. In the control method of the receiving end of the transmission apparatus in a mobile communication system, Initializing a second FIG unit and outputting coded frame data output from the convolutional encoder to a Viterbi decoder to decode the frame data; Removing a tail bit from the decoded frame data and outputting a frame from which the tail bit has been removed to a CRC checker to determine whether the frame data is non-recoverable and an error has occurred; Determining that the frame data error signal is retransmitted frame data if there is no frame data error signal, and reassembling the frame if retransmitted frame data is detected; Determining whether a data transmission termination signal has been input when the frame recombination is finished, and terminating the data transmission when the data transmission termination signal is input; Determining whether a data transmission termination signal is input if the frame data is not retransmitted as a result of the determination and terminating the data transmission if a data transmission termination signal is input; Generating a recognition number of the next frame and sending the received frame decoding step to a received frame decoding step if the data transmission termination signal is not input; And transmitting a frame retransmission request signal to a received frame decoding step if a frame data error signal is found as a result of the determination.