This paper describes a data transmission method using a cyclic redundancy check and inaudible frequencies.The proposed method uses inaudible high frequencies from 18 k Hz to 22 k Hz generated via the inner speaker of ...This paper describes a data transmission method using a cyclic redundancy check and inaudible frequencies.The proposed method uses inaudible high frequencies from 18 k Hz to 22 k Hz generated via the inner speaker of smart devices.Using the proposed method,the performance is evaluated by conducting data transmission tests between a smart book and smart phone.The test results confirm that the proposed method can send 32 bits of data in an average of 235 ms,the transmission success rate reaches 99.47%,and the error detection rate of the cyclic redundancy check is0.53%.展开更多
Polar codes represent one of the major breakthroughs in 5G standard,and have been proven to be able to achieve the symmetric capacity of binary-input discrete memoryless channels using the successive cancellation list...Polar codes represent one of the major breakthroughs in 5G standard,and have been proven to be able to achieve the symmetric capacity of binary-input discrete memoryless channels using the successive cancellation list(SCL)decoding algorithm.However,the SCL algorithm suffers from a large amount of memory overhead.This paper proposes an adaptive simplified decoding algorithm for multiple cyclic redundancy check(CRC)polar codes.Simulation results show that the proposed method can reduce the decoding complexity and memory space.It can also acquire the performance gain in the low signal to noise ratio region.展开更多
By exploiting the structural features of L1C messages,a novel Early Termination( ET) strategy is proposed to speed up the decoding of low-density parity-check( LDPC) codes in the GPS system. The proposed strategy is b...By exploiting the structural features of L1C messages,a novel Early Termination( ET) strategy is proposed to speed up the decoding of low-density parity-check( LDPC) codes in the GPS system. The proposed strategy is based on the cyclic redundancy check( CRC) of the messages in the subframes 2 and 3. The simulation results show that average number of iterations of the proposed strategy is less than that of the standard ET strategy,with nearly no degradation in decoding performance. Besides,the proposed ET strategy can be efficiently implemented in a sequential or parallel manner. Thus,the proposed ET strategy is attractive for practical purposes.展开更多
In order to change the path candidates, reduce the average list size, and make more paths pass cyclic redundancy check (CRC), multiple CRC-aided variable successive cancellation list (SCL) decoding algorithm is pr...In order to change the path candidates, reduce the average list size, and make more paths pass cyclic redundancy check (CRC), multiple CRC-aided variable successive cancellation list (SCL) decoding algorithm is proposed. In the decoding algorithm, the whole unfrozen bits are divided into several parts and each part is concatenated with a corresponding CRC code, except the last part which is concatenated with a whole unfrozen CRC code. Each CRC detection is performed, and only those satisfying each part CRC become the path candidates. A variable list is setup for each part to reduce the time complexity. Variable list size is setup for each part to reduce the time complexity until one survival path in each part can pass its corresponding CRC. The results show that the proposed algorithm can reduce the average list size, and the frame error rate (FER) performance, and has a better performance with the increase of the part number.展开更多
Computational Radio Frequency IDentification (CRFID) is a device that integrates passive sensing and computing applications,which is powered by electromagnetic waves and read by the off-the-shelf Ultra High Frequency ...Computational Radio Frequency IDentification (CRFID) is a device that integrates passive sensing and computing applications,which is powered by electromagnetic waves and read by the off-the-shelf Ultra High Frequency Radio Frequency IDentification (UHF RFID) readers.Traditional RFID only identifies the ID of the tag,and CRFID is different from traditional RFID.CRFID needs to transmit a large amount of sensing and computing data in the mobile sensing scene.However,the current Electronic Product Code,Class-1 Generation-2 (EPC C1G2)protocol mainly aims at the transmission of multi-tag and minor data.When a large amount of data need to be fed back,a more reliable communication mechanism must be used to ensure the efficiency of data exchange.The main strategy of this paper is to adjust the data frame length of the CRFID response dynamically to improve the efficiency and reliability of CRFID backscattering communication according to energy acquisition and channel complexity.This is done by constructing a dynamic data frame length model and optimizing the command set of the interface protocol.Then,according to the actual situation of the uplink,a dynamic data validation method is designed,which reduces the data transmission delay and the probability of retransmitting,and improves the throughput.The simulation results show that the proposed scheme is superior to the existing methods.Under different energy harvesting and channel conditions,the dynamic data frame length and verification method can approach the theoretical optimum.展开更多
基金supported by Ministry of Educationunder Basic Science Research Program under Grant No.NRF-2013R1A1A2061478
文摘This paper describes a data transmission method using a cyclic redundancy check and inaudible frequencies.The proposed method uses inaudible high frequencies from 18 k Hz to 22 k Hz generated via the inner speaker of smart devices.Using the proposed method,the performance is evaluated by conducting data transmission tests between a smart book and smart phone.The test results confirm that the proposed method can send 32 bits of data in an average of 235 ms,the transmission success rate reaches 99.47%,and the error detection rate of the cyclic redundancy check is0.53%.
基金supported by the National Key R&D Program of China(2018YFB2101300)the National Science Foundation of China(61973056)
文摘Polar codes represent one of the major breakthroughs in 5G standard,and have been proven to be able to achieve the symmetric capacity of binary-input discrete memoryless channels using the successive cancellation list(SCL)decoding algorithm.However,the SCL algorithm suffers from a large amount of memory overhead.This paper proposes an adaptive simplified decoding algorithm for multiple cyclic redundancy check(CRC)polar codes.Simulation results show that the proposed method can reduce the decoding complexity and memory space.It can also acquire the performance gain in the low signal to noise ratio region.
基金Sponsored by the National Natural Science Foundation of China(Grant No.61271423)
文摘By exploiting the structural features of L1C messages,a novel Early Termination( ET) strategy is proposed to speed up the decoding of low-density parity-check( LDPC) codes in the GPS system. The proposed strategy is based on the cyclic redundancy check( CRC) of the messages in the subframes 2 and 3. The simulation results show that average number of iterations of the proposed strategy is less than that of the standard ET strategy,with nearly no degradation in decoding performance. Besides,the proposed ET strategy can be efficiently implemented in a sequential or parallel manner. Thus,the proposed ET strategy is attractive for practical purposes.
基金supported by the National Natural Science Foundation of China (61475075,61271238)the Open Research Fund of Key Laboratory of Broadband Wireless Communication and Sensor Network Technology,Ministry of Education (NYKL2015011)
文摘In order to change the path candidates, reduce the average list size, and make more paths pass cyclic redundancy check (CRC), multiple CRC-aided variable successive cancellation list (SCL) decoding algorithm is proposed. In the decoding algorithm, the whole unfrozen bits are divided into several parts and each part is concatenated with a corresponding CRC code, except the last part which is concatenated with a whole unfrozen CRC code. Each CRC detection is performed, and only those satisfying each part CRC become the path candidates. A variable list is setup for each part to reduce the time complexity. Variable list size is setup for each part to reduce the time complexity until one survival path in each part can pass its corresponding CRC. The results show that the proposed algorithm can reduce the average list size, and the frame error rate (FER) performance, and has a better performance with the increase of the part number.
基金supported by the National Key Basic Research and Development Program of China(No.2018YFB2200900)the National Natural Science Foundation of China(Nos.61772358 and 61972273)the Transformation and Cultivation Project of Scientific and Technological Achievements of Universities in Shanxi Province。
文摘Computational Radio Frequency IDentification (CRFID) is a device that integrates passive sensing and computing applications,which is powered by electromagnetic waves and read by the off-the-shelf Ultra High Frequency Radio Frequency IDentification (UHF RFID) readers.Traditional RFID only identifies the ID of the tag,and CRFID is different from traditional RFID.CRFID needs to transmit a large amount of sensing and computing data in the mobile sensing scene.However,the current Electronic Product Code,Class-1 Generation-2 (EPC C1G2)protocol mainly aims at the transmission of multi-tag and minor data.When a large amount of data need to be fed back,a more reliable communication mechanism must be used to ensure the efficiency of data exchange.The main strategy of this paper is to adjust the data frame length of the CRFID response dynamically to improve the efficiency and reliability of CRFID backscattering communication according to energy acquisition and channel complexity.This is done by constructing a dynamic data frame length model and optimizing the command set of the interface protocol.Then,according to the actual situation of the uplink,a dynamic data validation method is designed,which reduces the data transmission delay and the probability of retransmitting,and improves the throughput.The simulation results show that the proposed scheme is superior to the existing methods.Under different energy harvesting and channel conditions,the dynamic data frame length and verification method can approach the theoretical optimum.