A new improved group space-time block code (G-STBC) based on constellation rotation for four transmit antennas was proposed. In comparison with the traditional G-STBC coding scheme, the proposed space-time code has lo...A new improved group space-time block code (G-STBC) based on constellation rotation for four transmit antennas was proposed. In comparison with the traditional G-STBC coding scheme, the proposed space-time code has longer code length and adopts proper rotation-based symbols, which can increase the minimum distance of space-time codes and thereby improve code gain and achieve full diversity performance. The simulation results verify that the proposed group space-time code can achieve better bit error performance than both the traditional group space-time code and other quasi-orthogonal space-time codes. Compared with Ma’s full diversity full rate (FDFR) codes, the proposed space-time code also can achieve the same excellent error performance. Furthermore, the design of the new space-time code gives another new and simple method to construct space-time codes with full diversity and high rate in case that it is not easy to design the traditional FDFR space-time codes.展开更多
A list sphere detector can use a smaller list than commonly believed by employing an appropriate soft output approximation method. Its effect on the “quality” of detector’s soft output value is evaluated by measuri...A list sphere detector can use a smaller list than commonly believed by employing an appropriate soft output approximation method. Its effect on the “quality” of detector’s soft output value is evaluated by measuring mutual information under ergodic channel. The result shows a length 40 list is adequate for a 4×4 16QAM MIMO system without system-level iteration. For the ergodic channel, the gain of a sphere detector over the linear MMSE detector is dependent on channel coding rate, which answers an important question when sphere detector should be used in system level design. All these theoretical results are then verified by Monte Carlo simulation.展开更多
基金National High Technology Research andDevelopment Program (863) of China( No. 003AA12331007 ) and NationalNatural Science Foundation of China(No. 60272079, 60332030)
文摘A new improved group space-time block code (G-STBC) based on constellation rotation for four transmit antennas was proposed. In comparison with the traditional G-STBC coding scheme, the proposed space-time code has longer code length and adopts proper rotation-based symbols, which can increase the minimum distance of space-time codes and thereby improve code gain and achieve full diversity performance. The simulation results verify that the proposed group space-time code can achieve better bit error performance than both the traditional group space-time code and other quasi-orthogonal space-time codes. Compared with Ma’s full diversity full rate (FDFR) codes, the proposed space-time code also can achieve the same excellent error performance. Furthermore, the design of the new space-time code gives another new and simple method to construct space-time codes with full diversity and high rate in case that it is not easy to design the traditional FDFR space-time codes.
基金National Natural Science Foundation ofChina(No.60332030)
文摘A list sphere detector can use a smaller list than commonly believed by employing an appropriate soft output approximation method. Its effect on the “quality” of detector’s soft output value is evaluated by measuring mutual information under ergodic channel. The result shows a length 40 list is adequate for a 4×4 16QAM MIMO system without system-level iteration. For the ergodic channel, the gain of a sphere detector over the linear MMSE detector is dependent on channel coding rate, which answers an important question when sphere detector should be used in system level design. All these theoretical results are then verified by Monte Carlo simulation.
