In this paper, Multiband-OFDM UWB system based on IEEE 802.15.3a standard is studied and simulated with spatial, time and frequency (STF)coding scheme. The using of STF coding method can guarantee both full symbol rat...In this paper, Multiband-OFDM UWB system based on IEEE 802.15.3a standard is studied and simulated with spatial, time and frequency (STF)coding scheme. The using of STF coding method can guarantee both full symbol rate and full diversity advantages. The simulation results show that the STF code uses multi- path-rich and random-clustering characteristics of UWB channel environment on the performance of MB- OFDM system.展开更多
A new non-orthogonal space-time-frequency code (STFC) was proposed. In conjunction with orthogonal frequency-division multiplexing (OFDM), it is appropriate for the application on frequency-selective fading channels. ...A new non-orthogonal space-time-frequency code (STFC) was proposed. In conjunction with orthogonal frequency-division multiplexing (OFDM), it is appropriate for the application on frequency-selective fading channels. On the basis of the existing non-orthogonal STC, frequency diversity is studied and a new non-orthogonal STFC is further designed. Monte-Carlo simulations show that the non-orthogonal STFC-OFDM has the advantage of large diversity order, high bandwidth efficiency and better BER performance when compared with the orthogonal STC/STFC-OFDM and non-orthogonal STC-OFDM systems.展开更多
A distributed space-time-frequency （STF） coding scheme is proposed for cooperative OFDM （C-OFDM） systems with three terminals over quasi-static frequency-selective Rayleigh fading channels, The outage probability ...A distributed space-time-frequency （STF） coding scheme is proposed for cooperative OFDM （C-OFDM） systems with three terminals over quasi-static frequency-selective Rayleigh fading channels, The outage probability is derived and its tight closed-form lower bound is presented. Asymptotic analysis indicates that the proposed scheme can achieve both spatial and multipath （frequency） diversity. The theoretical analysis of the proposed STF coded scheme is further implemented by the distributed group STF block coding （D-GSTFBC） scheme based on the subcarrier grouping technique, Simulation results confirm the previously introduced theoretical analysis.展开更多
For the frequency selective and time variant multiple-input multiple-output(MIMO)channel model taking into account transmitting and receiving antenna correlation,the diversity of space-time-frequency coded broadband o...For the frequency selective and time variant multiple-input multiple-output(MIMO)channel model taking into account transmitting and receiving antenna correlation,the diversity of space-time-frequency coded broadband orthogonal frequency division multiplexing(MIMO-OFDM)system is analyzed.Based on the average pairwise error probability(PEP),the design criterion of space-time-frequency code(STFC)is expanded.For a given STFC,it is found that the achievable diversity order is related to the transmitter and the receiver correlation matrix as well as the time correlation and frequency correlation matrix.The maximum available diversity of STFC over the correlation channel is Lrank(P)rank(Q)rank(RT).The space-time code and space-frequency code are special cases in our approach.Simulation results validate the findings.展开更多
The hybrid mobile satellite system operating in a single frequency network （SFN） mode is increasingly becoming attractive. The combination of satellite component （SC） and terrestrial component （TC） promises a be...The hybrid mobile satellite system operating in a single frequency network （SFN） mode is increasingly becoming attractive. The combination of satellite component （SC） and terrestrial component （TC） promises a better quality of service （QoS）. Multimedia broadcast and multicast services （MBMS） are expected to be prevailed in this kind of system. Several space frequency （SF） or space time （ST） codes have been proposed to enhance the system performance due to the lack of reverse link and omni-directional transmission. However, they mostly consider the system with only one SC and one TC and fail to make full use of available diversities. This paper presents a novel way to realize the dual polarization multiple input multiple output （MIMO） transmission by using the space time frequency （STF） code. The theoretical analysis and simulations indicate that the application of STF code can improve the system performance dramatically. A higher diversity gain can be achieved due to the cooperative transmission of SC and TC, while the coding gain can be enhanced by the reusing of STF code between SCs or TCs. Even if some of the links are lost, it can still work properly and benefit from the STF code. The relative relay can result in a degradation up to 0.5 dB in the coding gain.展开更多
文摘In this paper, Multiband-OFDM UWB system based on IEEE 802.15.3a standard is studied and simulated with spatial, time and frequency (STF)coding scheme. The using of STF coding method can guarantee both full symbol rate and full diversity advantages. The simulation results show that the STF code uses multi- path-rich and random-clustering characteristics of UWB channel environment on the performance of MB- OFDM system.
基金National Natural Science Foundation ofChina(No.60 3 72 0 76)
文摘A new non-orthogonal space-time-frequency code (STFC) was proposed. In conjunction with orthogonal frequency-division multiplexing (OFDM), it is appropriate for the application on frequency-selective fading channels. On the basis of the existing non-orthogonal STC, frequency diversity is studied and a new non-orthogonal STFC is further designed. Monte-Carlo simulations show that the non-orthogonal STFC-OFDM has the advantage of large diversity order, high bandwidth efficiency and better BER performance when compared with the orthogonal STC/STFC-OFDM and non-orthogonal STC-OFDM systems.
基金Supported by the Open Research Fund of National Mobile Communications Research Laboratory, Southeast University (Grant No. N200814)the National Natural Science Foundation of China (Grant No. 60672079)and the National High-Tech Research & Development Program ofChina (Grant No. 2009AA01Z249)
文摘A distributed space-time-frequency （STF） coding scheme is proposed for cooperative OFDM （C-OFDM） systems with three terminals over quasi-static frequency-selective Rayleigh fading channels, The outage probability is derived and its tight closed-form lower bound is presented. Asymptotic analysis indicates that the proposed scheme can achieve both spatial and multipath （frequency） diversity. The theoretical analysis of the proposed STF coded scheme is further implemented by the distributed group STF block coding （D-GSTFBC） scheme based on the subcarrier grouping technique, Simulation results confirm the previously introduced theoretical analysis.
基金supported by the National Natural Science Foundation of China (Grant Nos.60496310,60272046)the National Hi-Tech Research and Development Program of China (No.2002AA123031)+1 种基金the Natural Science Foundation of Jiangsu Province,China (No.BK2005061)the Grant of Ph.D Programs of Ministry of Education of China (No.20020286014).
文摘For the frequency selective and time variant multiple-input multiple-output(MIMO)channel model taking into account transmitting and receiving antenna correlation,the diversity of space-time-frequency coded broadband orthogonal frequency division multiplexing(MIMO-OFDM)system is analyzed.Based on the average pairwise error probability(PEP),the design criterion of space-time-frequency code(STFC)is expanded.For a given STFC,it is found that the achievable diversity order is related to the transmitter and the receiver correlation matrix as well as the time correlation and frequency correlation matrix.The maximum available diversity of STFC over the correlation channel is Lrank(P)rank(Q)rank(RT).The space-time code and space-frequency code are special cases in our approach.Simulation results validate the findings.
基金supported by the Hi-Tech Research and Development Program of China (2012AA01A506-4)
文摘The hybrid mobile satellite system operating in a single frequency network （SFN） mode is increasingly becoming attractive. The combination of satellite component （SC） and terrestrial component （TC） promises a better quality of service （QoS）. Multimedia broadcast and multicast services （MBMS） are expected to be prevailed in this kind of system. Several space frequency （SF） or space time （ST） codes have been proposed to enhance the system performance due to the lack of reverse link and omni-directional transmission. However, they mostly consider the system with only one SC and one TC and fail to make full use of available diversities. This paper presents a novel way to realize the dual polarization multiple input multiple output （MIMO） transmission by using the space time frequency （STF） code. The theoretical analysis and simulations indicate that the application of STF code can improve the system performance dramatically. A higher diversity gain can be achieved due to the cooperative transmission of SC and TC, while the coding gain can be enhanced by the reusing of STF code between SCs or TCs. Even if some of the links are lost, it can still work properly and benefit from the STF code. The relative relay can result in a degradation up to 0.5 dB in the coding gain.
