[PDF] Top 20 Performance evaluation of space-time-frequency spreading for MIMO OFDM-CDMA systems

... wireless systems must support mul- timedia services of a wide range of data rates with rea- sonable complexity, flexible multi-rate adaptation, and efficient multi-user multiplexing and ...generation ... See full document

... of CDMA and spread spectrum with OFDM in order to create a more robust modulation scheme that could survive frequency selective fading and thus OFDM- CDMA was ...born. ... See full document

... same time by spreading their information with preassigned signature ...However, CDMA suffers from “near-far” effect as well as implementation difficulties due to severe fading conditions ... See full document

... the spreading operation in the time-domain at each subcarrier ...ing frequency-selective fading, MCDS-CDMA requires forward error-correction coding and frequency-domain ...and ... See full document

... uses spreading technique that spreads information bearing signals, so that only intended receiver can able to receive it thus provides ...the spreading permutations based on STBC (space time ... See full document

... overall performance [30, 31]. Unlike centralized spreading code assignment strategies, a user is assigned a set of mutually orthogonal spreading codes and the transmitter decides which code or codes ... See full document

... recently, MIMO- OFDM schemes exploiting partial CSI have been proposed, encompassing the perfect CSI and no CSI ...on MIMO-OFDM channel estimation, there is very little development on channel ... See full document

... and OFDM. In this contribution, we discuss the generalized MC DS-CDMA system in- vestigated in [5], [6], where it has been shown that the generalized MC DS-CDMA scheme includes the subclasses of both ... See full document

... the performance of wideband code-division multiple-access (W-CDMA) systems using space-time- spreading- (STS-) based transmit diversity is investigated, when ... See full document

... cellular systems in terms of transmit power, complicacy in frequency of handover in high speed mobile environment (350km/h) and cell edge effect for transmission frequencies higher than 2 GHz, cellular ... See full document

... DS- CDMA system using space-time spreading [1] assisted transmit di- versity has been proposed and studied in ...DS-CDMA systems can be substantially increased, when using ... See full document

... through frequency-selective fading channels" such as the performance and capacity of space time block coded (STBC) multi-user CDMA system over Rayleigh fading channel condition ... See full document

... in MIMO–OFDM broadcast system with no CSI at the ...improved performance over STF. Simulations are made to evaluate the performance of the MIMO system in term of ...better ... See full document

... the OFDM/OQAM ...the MIMO Alamouti coding scheme with ...the CDMA spreading is carried out in the frequency domain, the Alamouti decoding scheme can only be applied if the channel is ... See full document

... communication systems in the next generation technologies are required to have high voice quality and also need to provide higher data ...same time they need to operate in different types of environments ... See full document

... nication systems is limited by the time-varying characteristics of the ...the time- varying effects of wireless channels is employing ...years, space-time coding has received much ... See full document

... extending OFDM systems to much higher data rates by adopting MIMO smart antenna technique system ...the MIMO-OFDM system with subcarriers used over MIMO frequency ... See full document

... From June 1997 to December 1997, he was a Vis- iting Scientist at the Institute of Radio Engineering and Electronics, Academy of Sciences of the Czech Republic, Prague. Since December 1997, he has been with the ... See full document

... an OFDM block and the number of outages per ...across frequency. This characterization of the system across frequency is the focus of this ...the frequency domain and compute LCRs and ...the ... See full document

... PERFORMANCE RESULTS In this section the BER performance of the downlink of a generalized MC DS-CDMA system employing SSTS and using 32-chip Walsh codes as T-domain spreading sequences as[r] ... See full document