Multiple-input multiple-output (MIMO) modeling through the use of orthogonal frequency division multiplexing (OFDM) offers a viable alternative to reduce bandwidth and simultaneously improves the quality of service of...
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Multiple-input multiple-output (MIMO) modeling through the use of orthogonal frequency division multiplexing (OFDM) offers a viable alternative to reduce bandwidth and simultaneously improves the quality of service of wireless mobile communication. One of the major concerns in the MIMO-OFDM system is the high peak-to-average power ratio (PAPR). In this article, a combinational scheme, active partial sequence (APS), is proposed to combat PAPR in MIMO-OFDM under Rayleigh fading environment. The key idea of the APS method is to combine the approximate gradient project followed by partial transmit sequence technique. The simulation results show that the proposed method achieves a significant reduction in PAPR and maintains the same data rate without sacrificing the BER performance over other conventional techniques.
This paper analyzes the block error rate (BLER) performance provided by a virtual MIMO scheme which implements a modified Alamouti space-frequencyblock Code (SFBC) encoding-decoding algorithm using two fixed Decode &...
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ISBN:
(纸本)9781479985050
This paper analyzes the block error rate (BLER) performance provided by a virtual MIMO scheme which implements a modified Alamouti space-frequencyblock Code (SFBC) encoding-decoding algorithm using two fixed Decode &Forward relays that perform selective relaying, and single antenna devices. It also analyzes the performance of the classical relay-based distributed Alamouti scheme with single-antenna devices and, as baseline, by the non-cooperative Alamouti scheme which uses an antenna array at the source. We present the theoretical derivations of the BLER provided by the three schemes vs. the SNRs of the employed channels, using an approximation of the BLER ensured by the channel code used on each constituent link and validate them by computer simulation, both for the downlink and uplink transmissions of a generic cellular network, over Rayleigh block-faded channels, for various positions of the user terminal vs. the base station and relays.
LTE has been developed for low latencies, high data rates and greater spectral efficiency. To provide best quality signal in LTE in Downlink, the diversity schemes are employed that too space diversity schemes most wi...
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ISBN:
(纸本)9781467398251
LTE has been developed for low latencies, high data rates and greater spectral efficiency. To provide best quality signal in LTE in Downlink, the diversity schemes are employed that too space diversity schemes most widely used. In space diversity schemes transmit diversity is preferred over the receiver diversity schemes. In this paper data is generated in accord with 3GPP standards and it is transmitted by employing both transmit diversity and receiver diversity and the performance is examined with respect to the data received. For receiver diversity maximal ratio receiver combining is used and for transmit diversity space frequency block coding is used.
This paper presents a joint channel estimation and data detection (JCEDD) for multiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) system. Initial estimate of the channel is obtained...
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ISBN:
(纸本)9781479930807
This paper presents a joint channel estimation and data detection (JCEDD) for multiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) system. Initial estimate of the channel is obtained using semi-blind channel estimation (SBCE). The whitening rotation (WR) based orthogonal pilot maximum likelihood (OPML) method is used to obtain the channel estimate. The estimate is further enhanced by extracting information through the received data symbols. The performance of the proposed estimator is studied under various channel models. The simulation study shows that this approach clearly outperforms the TBCE and OPML SBCE methods but at the cost of higher computational complexity
This paper proposes applying precoding vector switching (PVS) transmit diversity scheme for primary broadcast channel (P-BCH) and secondary synchronization channel (S-SCH) in OFDM-based E-UTRA systems. The S-SCH is us...
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ISBN:
(纸本)1424402638;9781424402632;1424402646
This paper proposes applying precoding vector switching (PVS) transmit diversity scheme for primary broadcast channel (P-BCH) and secondary synchronization channel (S-SCH) in OFDM-based E-UTRA systems. The S-SCH is used as phase reference for P-BCH demodulation, which results in making no blind detection of the number of transmit antennas. Performance comparison is made with space frequency block coding (SFBC) using common reference signal (RS) as phase reference.
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