This paper presents performance comparison of various modulation techniques in Rayleigh fading channel. In the comparison, the space time coding has been used. The performance comparison are made on the basis of bit error rate(BER) and symbol error rate(SER) performance matrices over Rayleigh fading channel with BPSK,QPSK,8PSK and QAM modulation technique. The comparison results shows that in R...

Due to the increased demand of wireless communication systems because of the features of the system which provides a wide coverage, high throughput and reliable services, the MIMO systems communication has come into existence. Features provided by these systems ensure the improved system coverage and increased data transmission rate by considering multiple numbers of transmitter and receiver an...

An efficient use of the radio resources in wireless communications presents a fundamental challenge. While power is one of the most important radio resources, and its control has been studied extensively for voice communications, the increase demand of wireless data service makes it very important to establish power control algorithms for such service. In Code Division Multiple Access (CDMA) ce...

Transmission of continuous media such as video over time-varying wireless communication channels can benefit from the use of adaptation techniques in both source and channel coding. An adaptive feedback-based wireless video transmission scheme is investigated in this research with special emphasis on feedback-based adaptation. To be more specific, an interactive adaptive transmission scheme is ...

In this paper, a low complexity and efficient multi-user Space Time Block Code Multi-Carrier Code Division Multiple Access (STBC MC-CDMA) for downlink wireless communication system is proposed. STBC MC-CDMA provides diversity gain to improve transmission efficiency of mobile wireless systems where both STBC encoder and decoder are in time domain thus reducing the complexity at the receiver side...

This paper discusses the analysis and simulation of a technique for combating the ffects of multipath propagation and cochannel interference on a narrow-band digital mobile channel. This system uses the discrete Fourier transform to orthogonally frequency multiplex many narrow subchannels, each signaling at a very low rate, into one high-rate channel. When this technique is used with pilot-base...

Channel estimation is crucial for massive massive multiple-input multiple-output (MIMO) systems to scale up multi-user (MU) MIMO, providing great improvement in spectral and energy efficiency. This paper presents a simple and practical channel estimator for multi-cell MU massive MIMO time division duplex (TDD) systems with pilot contamination in flat Rayleigh fading channels, i.e., the gains of...

Multi-carrier code division multiple access (MCCDMA) is method for high speed data rate communication. It skip the problem of inter symbol interference.MC-CDMA too provide spatial diversity, which mitigate the fading. The usage of MC-CDMA can significantly improve the performance of wireless communication system. This paper presents the simulation of MC-CDMA system performance with MSK modulati...

Abstruct-Multiple trellis-coded modulation (MTCM) of MPSK employs separate designs, which are optimum at high SNR, for the Rayleigh fading channel and the AWGN channel, in order to meet the different design criteria for the two channels. The separate designs are no longer optimum if the channel conditions are interchanged, if the channel is Rician, or if the SNR’s are moderate. In this paper, a...

In this paper, a comparative estimate of the channel capacity assigned to each user for frequencydivision multiple-access (FDMA) and direct-sequence code-division multiple-access (DS-CDMA) schemes operating in a Rayleigh fading channel is presented. Then, the achievable channel capacity per user (in the Shannon sense) is estimated in an average sense considering the inherent diversity potential...