There are parallel channels which are not fully connected in practice, such as Frequency Division Multiplex (FDM or Orthogonal FDM) systems. Conventional space-time codes can be used for such parallel channels but not...There are parallel channels which are not fully connected in practice, such as Frequency Division Multiplex (FDM or Orthogonal FDM) systems. Conventional space-time codes can be used for such parallel channels but not the optimal. Based on the derivation of PEP expression for codes transmitted on parallel block fading channels, criteria of codes design for not fully connected channels are proposed and are compared with Tarokh's criteria for fully connected channel. New codes for such channels are provided by systematical and exhaustive search. Simulation results show that these codes offer better performance on parallel FDM channels than other known codes.展开更多
A new space-time block codes based on quasi-orthogonal designs are put forward. First the channel model is formulated. Then the connection between orthogonal /quasi-orthogonal designs and space-time block codes is exp...A new space-time block codes based on quasi-orthogonal designs are put forward. First the channel model is formulated. Then the connection between orthogonal /quasi-orthogonal designs and space-time block codes is explored. Finally we make simulations for the transmission of 4 bits/s/Hz and 6 bits/s/Hz using eight transmit antennas using the rate 3/4 quasi-orthogonal space-time block code and the rate 1/2 full-diversity orthogonal space-time block code. Simulation results show that full transmission rate is more important for very low signal noise ratio (SNR) and high bit error probability (BEP), while full diversity is more important for very high SNR and low BEP.展开更多
基金Supported by the National Natural Science Foundation of China(No.60496311).
文摘There are parallel channels which are not fully connected in practice, such as Frequency Division Multiplex (FDM or Orthogonal FDM) systems. Conventional space-time codes can be used for such parallel channels but not the optimal. Based on the derivation of PEP expression for codes transmitted on parallel block fading channels, criteria of codes design for not fully connected channels are proposed and are compared with Tarokh's criteria for fully connected channel. New codes for such channels are provided by systematical and exhaustive search. Simulation results show that these codes offer better performance on parallel FDM channels than other known codes.
文摘A new space-time block codes based on quasi-orthogonal designs are put forward. First the channel model is formulated. Then the connection between orthogonal /quasi-orthogonal designs and space-time block codes is explored. Finally we make simulations for the transmission of 4 bits/s/Hz and 6 bits/s/Hz using eight transmit antennas using the rate 3/4 quasi-orthogonal space-time block code and the rate 1/2 full-diversity orthogonal space-time block code. Simulation results show that full transmission rate is more important for very low signal noise ratio (SNR) and high bit error probability (BEP), while full diversity is more important for very high SNR and low BEP.
