This paper proposes a novel LDPC based differential unitary space-frequency coding (DUSFC) scheme for MIMO-OFDM systems when neither the transmitter nor the receiver has access to the channel state information (CSI). ...This paper proposes a novel LDPC based differential unitary space-frequency coding (DUSFC) scheme for MIMO-OFDM systems when neither the transmitter nor the receiver has access to the channel state information (CSI). The new DUSFC strategy basically consists of coding across transmit antennas and OFDM tones simultaneously as well as differential modulation in the time-domain. It can fully exploit the inherent advantages provided by the multipath fading channels, resulting in a high degree of diversity. The state-of-the-art low-density parity-check (LDPC) codes are concatenated with our DUSFC as channel coding to improve the bit error rate (BER) performance considerably. Owing to the maximum multipath diversity and large coding advantages, LDPC-DUSFC strongly outperforms the differential unitary space-time coded OFDM techniques re- cently proposed in literature. The corresponding iterative decoding algorithm without channel estimation is finally provided to offer significant performance gain. Simulation results illustrate the merits of the proposed scheme.展开更多
Shannon channel capacity theorem poses highest bit-rate of error free transmission over additive white Gaussian noise channel.In addition,he proved that there exists channel code that can theoretically achieve the cha...Shannon channel capacity theorem poses highest bit-rate of error free transmission over additive white Gaussian noise channel.In addition,he proved that there exists channel code that can theoretically achieve the channel capacity.Indeed fortunately,the latter researchers found some practical channel codes approaching the channel capacity with insignificant losses of spectral efficiency under ignorable bit error rate(BER).The authors note,in general,that bits of the channel codes are not independent of each other in code space.Further,we note that the modulated symbols are not independent among them,as well,in Euclidean Space.By exploiting a usage of the dependencies jointly to signal design,we can transmit two independent signal streams through an additive white Gaussian channel and separate them in Euclidean space at the receiver.The capacity of this approach is found larger than that of Shannon capacity in the same channel assumptions.The numerical results confirm the theoretical procedures.展开更多
基金Project (No. 60272079) supported by the National Natural Sci-ence Foundation of China
文摘This paper proposes a novel LDPC based differential unitary space-frequency coding (DUSFC) scheme for MIMO-OFDM systems when neither the transmitter nor the receiver has access to the channel state information (CSI). The new DUSFC strategy basically consists of coding across transmit antennas and OFDM tones simultaneously as well as differential modulation in the time-domain. It can fully exploit the inherent advantages provided by the multipath fading channels, resulting in a high degree of diversity. The state-of-the-art low-density parity-check (LDPC) codes are concatenated with our DUSFC as channel coding to improve the bit error rate (BER) performance considerably. Owing to the maximum multipath diversity and large coding advantages, LDPC-DUSFC strongly outperforms the differential unitary space-time coded OFDM techniques re- cently proposed in literature. The corresponding iterative decoding algorithm without channel estimation is finally provided to offer significant performance gain. Simulation results illustrate the merits of the proposed scheme.
基金supported by two Programs of National Natural Science Foundation of China(No.61271203 and No.61531004)
文摘Shannon channel capacity theorem poses highest bit-rate of error free transmission over additive white Gaussian noise channel.In addition,he proved that there exists channel code that can theoretically achieve the channel capacity.Indeed fortunately,the latter researchers found some practical channel codes approaching the channel capacity with insignificant losses of spectral efficiency under ignorable bit error rate(BER).The authors note,in general,that bits of the channel codes are not independent of each other in code space.Further,we note that the modulated symbols are not independent among them,as well,in Euclidean Space.By exploiting a usage of the dependencies jointly to signal design,we can transmit two independent signal streams through an additive white Gaussian channel and separate them in Euclidean space at the receiver.The capacity of this approach is found larger than that of Shannon capacity in the same channel assumptions.The numerical results confirm the theoretical procedures.