Single carrier frequency division multiple access (SCFDMA) is one well-known scheme, which has recently become a preferred choice for uplink channels. Due to the usage of single carrier, the performance of SC-FDMA systems degrades in deep frequency selective fading channels. In this paper, we propose a structure of equalizer based on frequency domain decision feedback which could be used for mu...

Channel estimation in communication systems is one of the most important issues that can reduce the error rate of sending and receiving information as much as possible. In this regard, estimation of OFDM-based wireless channels using known sub-carriers as pilot is of particular importance in frequency domain. In this paper, channel estimation under short cyclic prefix (CP) in OFDM system is con...

We propose a downlink multiple-input multipleoutput (MIMO) multi-carrier code division multiple access (MCCDMA) system with adaptive beamforming algorithm for smart antennas. The algorithm used in this paper is based on the Least Mean Square (LMS), with pilot channel estimation (PCE) and the zero forcing equalizer (ZFE) in the receiver, requiring reference signal and no knowledge channel. MC-CD...

A large demand of frequency allocation has fuelled the Multi-carrier system, resulting in a crowded spectrum as well as simultaneous access being required by a large number of users. Existing wireless systems may utilize single frequency, single antenna and pulse for carrier transmission and reception. Problems of such system is that in case of failure the total system will become non operation...

To allow for a computationally efficient equalization scheme for the frequencyselective transmission channels encountered in wireless local area network (WLAN) applications, cyclic prefix (CP) block transmission schemes have been proposed, such as single-carrier CP (SC-CP) and multi-carrier CP (MC-CP) transmission, also known as orthogonal frequency division multiplexing (OFDM). In this letter,...

This paper investigates a downlink multiple-input multiple-output (MIMO) multi-carrier code division multiple access (MC-CDMA) system with pilot aided channel estimation (PACE) and iterative channel estimation (ICE) in the receiver. Due to the superposition of different users’ spread data signals, zero-valued chips can occur after spreading, which can cause noise enhancement when using data est...

The aim of this survey is to investigate channel estimation method with carrier frequency offset in MIMO-OFDM systems. According to this, using maximum likelihood estimation algorithm (MLE), the carrier frequency offset (CFO) can be estimated. Then we estimate channel's coefficients for these systems. To accurately estimate the channel's coefficients, carrier frequency offset mitigati...

The Carrier Frequency Offset (CFO) due to timevarying fading channel is the main cause of the loss of orthogonality among OFDM subcarriers which is linked to inter-carrier interference (ICI). Hence, it is necessary to precisely estimate and compensate the CFO. Especially for mobile broadband communications, CFO and channel gain also have to be estimated and tracked to maintain the system perfor...

To support high data rate wireless communications, in this paper, based on the linearly constrained constant modulus (LCCM) criterion, the reverse link performance of the multi-carrier code division multiple access (MC-CDMA) receiver, with frequency combiner, and having smart antenna arrays beamformer in base station, has been investigated over the Rayleigh fading channel. By using the Kronecke...

Channel estimation is one of the most significant technologies in orthogonal-frequency-divisionmultiplexing(OFDM) . Inter-carrier-interference (ICI) occurs in OFDM which must be removed. There are various methods to reduce ICI in OFDM . Channel estimation techniques are used to investigate to reduce ICI in OFDM .In this paper we will discuss Channel estimation methods and DFT based channel esti...