Reducing the PAPR by utilisation of the LDPC code

Abstract

Social cues, such as eye gaze and pointing fingers, can increase the prioritisation of specific locations for cognitive processing. A previous study using a manual reaching task showed that, although both gaze and pointing cues altered target prioritisation (reaction times [RTs]), only pointing cues affected action execution (trajectory deviations). These differential effects of gaze and pointing cues on action execution could be because the gaze cue was conveyed through a disembodied head; hence, the model lacked the potential for a body part (i.e., hands) to interact with the target. In the present study, the image of a male gaze model, whose gaze direction coincided with two potential target locations, was centrally presented. The model either had his arms and hands extended underneath the potential target locations, indicating the potential to act on the targets (Experiment 1), or had his arms crossed in front of his chest, indicating the absence of potential to act (Experiment 2). Participants reached to a target that followed a nonpredictive gaze cue at one of three stimulus onset asynchronies. RTs and reach trajectories of the movements to cued and uncued targets were analysed. RTs showed a facilitation effect for both experiments, whereas trajectory analysis revealed facilitatory and inhibitory effects, but only in Experiment 1 when the model could potentially act on the targets. The results of this study suggested that when the gaze model had the potential to interact with the cued target location, the model's gaze affected not only target prioritisation but also movement execution.

Efficiency of the LDPC Codes in the Reduction of PAPR in Comparison to Turbo Codes and Concatenated Turbo-Reed Solomon Codes in a MIMO-OFDM System

“…COMPARISON OF CODING TECHNIQUES USED TO REDUCE THE PAPR PROBLEM Low density parity check codes [1] (LDPC) were the first codes to allow data transmission rates close to the theoretical maximum, the Shannon limit. Turbo codes are nowadays competing with LDPC codes which provide similar performance.…”

“…Several techniques have been proposed to reduce the high PAPR. In order to reduce the PAPR [1][2] of OFDM systems, many schemes were proposed, among which coding schemes are the most attractive ones due to their inherent error control capability and the simplicity of implementation. The efficiency of the LDPC codes has been compared with turbo codes and concatenated turbo-Reed Solomon codes in a MIMO-OFDM system in this paper.…”

Robotic Mobile System's Performance-Based MIMO-OFDM Technology

“…After the IFFT stage and due to the coherent addition of the independently modulated subcarriers to produce OFDM symbol, a large PAPR ratio could appear. Thus we try to reduce the effect of these peaks by applying the PDNN and then compare it to the achieved results from our previously published work of using linear coding techniques [11,16,17]. Subsection A describes the MIMO-OFDM-based PDNN systems, while Subsection B gives a brief overview of the previously published work to combat the PAPR problem.…”

“…Therefore, the PAPR will decrease if the average power of the OFDM symbol is decreased. This mathematical derivation was the basis of our previously published work to combat the effect of the PAPR drawback on the MIMO-OFDM systems [11,16,17].…”

“…In [10,16,17], different linear coding techniques have been used to accomplish the aim of reducing PAPR, such as convolutional encoding, LDPC codes and turbo coding. The period of the affected symbol will be spread according to the chosen spreading rate, to be "I" times the original one, where "I" is the spreading rate.…”