In this paper we have investigated the performance of downlink generalized distributed antenna system （GDAS）. Under the assumption of spatial correlated fading conditions, we have derived the numeric expression of c...In this paper we have investigated the performance of downlink generalized distributed antenna system （GDAS）. Under the assumption of spatial correlated fading conditions, we have derived the numeric expression of correlated coefficients according to series of Bessel function, and have lifted the range restriction of the mean angle of incident. Moreover, the architecture of distributed generalized layered space time codes （GLST） has been considered in order to achieve both multiplexing gain and diversity gain while we have used basis vector from null space instead of orthogonal set to obtain the same system performance but with lower complexity. Furthermore, in order to maximize the capacity, Gerschgorin circles based fast antenna selection algorithms have been evaluated including a discussion of those simulation results.展开更多
Conventional adaptive transmission schemes perform poorly in wireless correlated slow-fading channels.A cross-layer adaptive transmission scheme combined with selective repeat automatic repeat request(SR-ARQ)is propos...Conventional adaptive transmission schemes perform poorly in wireless correlated slow-fading channels.A cross-layer adaptive transmission scheme combined with selective repeat automatic repeat request(SR-ARQ)is proposed.We apply a multi-state Markov system model for analyzing the performance of systems and optimizing the selection of modulation levels and packet sizes in correlated fading channels,which is also described by a finite-state Markov chain.A general closed-form expression of the average throughput for our suggested scheme is presented.Numerical results show that our adaptive scheme combined with SR-ARQ can obtain good performance in correlated fading channels.展开更多
基金Supported by the Hi-Tech Research and Development Program of China (2009AA011502)China Important National Science &Technology Specific Projects (2009ZX03007-003-01)the National Natural Science Foundation of China (60772113)
文摘In this paper we have investigated the performance of downlink generalized distributed antenna system （GDAS）. Under the assumption of spatial correlated fading conditions, we have derived the numeric expression of correlated coefficients according to series of Bessel function, and have lifted the range restriction of the mean angle of incident. Moreover, the architecture of distributed generalized layered space time codes （GLST） has been considered in order to achieve both multiplexing gain and diversity gain while we have used basis vector from null space instead of orthogonal set to obtain the same system performance but with lower complexity. Furthermore, in order to maximize the capacity, Gerschgorin circles based fast antenna selection algorithms have been evaluated including a discussion of those simulation results.
基金supported by the National Natural Science Foundation of China(Grant Nos.90204004,60402012)the National Basic Research Program of China(No.2003CB314806)the China Postdoctoral Science Foundation(No.2003034111).
文摘Conventional adaptive transmission schemes perform poorly in wireless correlated slow-fading channels.A cross-layer adaptive transmission scheme combined with selective repeat automatic repeat request(SR-ARQ)is proposed.We apply a multi-state Markov system model for analyzing the performance of systems and optimizing the selection of modulation levels and packet sizes in correlated fading channels,which is also described by a finite-state Markov chain.A general closed-form expression of the average throughput for our suggested scheme is presented.Numerical results show that our adaptive scheme combined with SR-ARQ can obtain good performance in correlated fading channels.
