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
To design the terminal maneuver strategy of an anti-ship missile,first,the analytical solution of miss distance when an anti-ship missile has planar weaving maneuver and three-dimension spiral maneuver is presented,in...To design the terminal maneuver strategy of an anti-ship missile,first,the analytical solution of miss distance when an anti-ship missile has planar weaving maneuver and three-dimension spiral maneuver is presented,in which not only the amplitude and frequency are considered but also the initial phase is taken into account.Next,based on the analytical solution of miss distance,the effects on the miss distance of the amplitude,frequency,initial phase of the anti-ship missile＇s maneuver acceleration and the order of flight control system of the air-ship missile are analyzed.Finally,the optimum weaving maneuver and spiral maneuver which make the miss distance be the largest under some conditions are designed,which is of important meaning for increasing the survival probability of the anti-ship missile.展开更多
To improve the error correction performance, an innovative encoding structure with tail-biting for spinal codes is designed. Furthermore, an adaptive forward stack decoding(A-FSD) algorithm with lower complexity for s...To improve the error correction performance, an innovative encoding structure with tail-biting for spinal codes is designed. Furthermore, an adaptive forward stack decoding(A-FSD) algorithm with lower complexity for spinal codes is proposed. In the A-FSD algorithm, a flexible threshold parameter is set by a variable channel state to narrow the scale of nodes accessed. On this basis, a new decoding method of AFSD with early termination(AFSD-ET) is further proposed. The AFSD-ET decoder not only has the ability of dynamically modifying the number of stored nodes, but also adopts the early termination criterion to curtail complexity. The complexity and related parameters are verified through a series of simulations. The simulation results show that the proposed spinal codes with tail-biting and the AFSD-ET decoding algorithms can reduce the complexity and improve the decoding rate without sacrificing correct decoding performance.展开更多
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 Ministerial Level Advanced Research Foundation(0528)
文摘To design the terminal maneuver strategy of an anti-ship missile,first,the analytical solution of miss distance when an anti-ship missile has planar weaving maneuver and three-dimension spiral maneuver is presented,in which not only the amplitude and frequency are considered but also the initial phase is taken into account.Next,based on the analytical solution of miss distance,the effects on the miss distance of the amplitude,frequency,initial phase of the anti-ship missile＇s maneuver acceleration and the order of flight control system of the air-ship missile are analyzed.Finally,the optimum weaving maneuver and spiral maneuver which make the miss distance be the largest under some conditions are designed,which is of important meaning for increasing the survival probability of the anti-ship missile.
基金supported by the National Natural Science Foundation of China (61701020)the Scientific and Technological Innovation Foundation of Shunde Graduate School,USTB (BK19BF009)。
文摘To improve the error correction performance, an innovative encoding structure with tail-biting for spinal codes is designed. Furthermore, an adaptive forward stack decoding(A-FSD) algorithm with lower complexity for spinal codes is proposed. In the A-FSD algorithm, a flexible threshold parameter is set by a variable channel state to narrow the scale of nodes accessed. On this basis, a new decoding method of AFSD with early termination(AFSD-ET) is further proposed. The AFSD-ET decoder not only has the ability of dynamically modifying the number of stored nodes, but also adopts the early termination criterion to curtail complexity. The complexity and related parameters are verified through a series of simulations. The simulation results show that the proposed spinal codes with tail-biting and the AFSD-ET decoding algorithms can reduce the complexity and improve the decoding rate without sacrificing correct decoding performance.
