A joint OFDM PAPR reduction and data decoding scheme with no SI estimation

The need for side information (SI) estimation poses a major challenge when selected mapping (SLM) is implemented to reduce peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM) systems. Recent studies on pilot-assisted SI estimation procedures suggest that it is possible to determine the SI without the need for SI transmission. However, SI estimation adds to computational complexity and implementation challenges of practical SLM-OFDM receivers. To address these technical issues, this paper presents the use of a pilot-assisted cluster-based phase modulation and demodulation procedure called embedded coded modulation (ECM). The ECM technique uses a slightly modified SLM approach to reduce PAPR and to enable data recovery with no SI transmission and no SI estimation. In the presence of some non-linear amplifier distortion, it is shown that the ECM method achieves similar data decoding performance as conventional SLM-OFDM receiver that assumed a perfectly known SI and when the SI is estimated using a frequency-domain correlation approach. However, when the number of OFDM subcarriers is small and due to the clustering in ECM, the modified SLM produces a smaller PAPR reduction gain compared with conventional SLM

Performance of PAPR Reduction Techniques for MIMO-OFDM Systems in 4G Wireless Communication

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Computationally Efficient Modified PTS for PAPR Reduction in MIMO-OFDM

Nowadays wireless communication has taken its leap for a high data rate using the multi-carrier transmission technique.Orthogonal frequency division multiplexing(OFDM) is one of such popular method for achieving this high information rate.OFDM has several advantages,but one of the main drawbacks is its high peak-to-average power ratio(PAPR).This is due to a large number of the subcarrier,which leads to distortion problem at receiver. An OFDM signal with the high PAPR requires power amplifier’s(PAs)with large dynamic ranges.Such PAs are less efficient,costly to manufacture and very much difficult to design.There have been a large number of techniques are available in the literature to reduce the PAPR, such as Partial transmit sequence,Selective mapping,Block Coding, Tone rejection,etc.However,the challenging part is that most of the PAPR reduction schemes come with high computational complexity.Recent PAPR reduction techniques such as partial transmit sequence(PTS)has been considered as most popular for PAPR reduction.This research work explores to find a solution for the PAPR reduction by using PTS technique, which has been implemented by using sub-blocks partitioning.In sub-block partition consists of OFDM data frame which is partitioned into several sub-blocks.An adjacent partitioning(AP)method can be perceived as the best of the existing partitioning method when the cost and PAPR reduction performance are considered together.A new technique is based on modified PTS using phase rotation and circular shifting to attain the overall reduction of PAPR in MIMO-OFDM system, but computational complexity does not decrease for the same.A Co-operative PTS technique which is mainly based on alternative PTS technique is applied.In this technique although a slight loss of PAPR reduction performance is there but with much lower computational complexity

Adjacent Partitioning Based MIMO-OFDM System with Partial Transmit Sequence for PAPR Reduction

The multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) transmission approach has been chosen to be a standard of fourth-generation (4G) wireless communication systems, but it has to cope with the main disadvantages and challenges of OFDM-based techniques, including the high peak-to-average power ratio (PAPR). Peak to average power ratio (PAPR) being a predictable random variable in multicarrier system and it can be minimized by different techniques. Complementary cumulative distribution function (CCDF) is used to describe the PAPR appropriately. Partial transmit sequence (PTS) is an attractive distortion less peak-to-average power ratio (PAPR) reduction technique for orthogonal frequency division multiplexing (OFDM) system. In this paper the performance of one of scrambling technique called partial transmit sequence (PTS) in MIMO-OFDM system and adjacent partitioning(one of the partitioning technique) in MIMO-OFDM system with PTS are analyzed based on the characteristics of CCDF DOI: 10.17762/ijritcc2321-8169.150514