Analysis of Peak‐to‐Average Power Ratio in OFDM Systems Using Cognitive Radio Technology

2020 ◽  
pp. 179-202
Author(s):  
Udayakumar Easwaran ◽  
Poongodi Palaniswamy ◽  
Vetrivelan Ponnusamy
Keyword(s):  
Cognitive Radio ◽  
Average Power ◽  
Power Ratio ◽  
Ofdm Systems ◽  
Radio Technology ◽  
Cognitive Radio Technology

scholarly journals Peak-to-Average Power Ratio reduction in Wavelet based OFDM using Modified Selective Mapping for Cognitive Radio Applications

2021 ◽  
Vol 18 (12) ◽  
Author(s):  
Arjun K R ◽  
Surekha T P
Keyword(s):  
Quality Of Service ◽  
Cognitive Radio ◽  
Linear Part ◽  
Cognitive Radios ◽  
Average Power ◽  
Power Ratio ◽  
Ofdm Systems ◽  
Radio System ◽  
Selective Mapping

The prospect of guaranteed quality of service for primary and secondary users in the expression of regulated Peak-to-Average Power Ratio (PAPR) and Bit Error Rate (BER) can be increased in Cognitive Radios using Wavelet based OFDM systems which localize spectrum in realms of time and frequency. However, cutting the Gordian knot of high PAPR associated with the Multi-Carrier Modulation schemes to operate in the linear part of the power amplifier nourishing the balance between PAPR and BER is difficult. In this paper, the phase of the subcarriers is altered by a value of finite, equally spaced phase shifts. The frame of Wavelet-based OFDM (WOFDM) with minimum PAPR guarantees the minimum quality of service (QoS) in terms of Throughput. BER is then identified and transmitted. This modification is applied to various Wavelets and compared amongst WOFDM and FFT-based OFDM schemes. The novelty of this paper lies in using Hadamard and/or Toeplitz matrix to generate phase sequences in a modified SLM technique of Wavelet-based OFDM systems while maintaining the minimum required QoS in Cognitive Radios. The result shows that the proposed technique reduces the PAPR compared to unmodified SLM techniques. HIGHLIGHTS Wavelet based OFDM systems localize spectrum in realms of time and frequency The sinusoid bases function in OFDM has been replaced by Wavelet bases Selective Mapping (SLM) is a popular technique towards PAPR reduction The primary function of the Cognitive Radio system is to identify the spectrum holes GRAPHICAL ABSTRACT

PAPR reduction using OQAM for spectrum sensing

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Renuka N. ◽  
Satya Sairam M.
Keyword(s):  
Cognitive Radio ◽  
Pulse Shape ◽  
Average Power ◽  
Multicarrier Modulation ◽  
Energy Transmission ◽  
Content Type ◽  
Spectral Leakage ◽  
Band Energy ◽  
Radio Technology ◽  
Cognitive Radio Technology

Purpose The tremendous growth of wireless applications and the demand for high data rate, the spectrum utilization improvement has been the most crucial challenges for wireless communication. Adapting cognitive radio with orthogonal frequency division multiplexing or offset quadrature amplitude modulation (OFDM/OQAM) improves the spectrum and energy efficiencies. Design/methodology/approach Thus, it overcomes the spectral leakage problem at the transmitter side and leads to less interference from secondary user (SUs) to primary user (PUs) and between the SUs in cognitive radio technology. The benefit of exploiting pulse shape filtering in the OFDM/OQAM is to not only eliminate the requirement of the guard bands but also reduce the out of band energy transmission, which also improves the spectral isolation from the neighboring systems. But the high peak to average power ratio (PAPR) phenomenon is a common issue in the majority of the multicarrier modulation systems and thus OFDM/OQAM is no exception in this case. Findings Therefore, this paper aims to examine the effect of integrating the Walsh–Hadamard Transform (WHT) on the power spectral density and investigates the problem of PAPR in the WHT/OQAM system. Originality/value Thus, it overcomes the spectral leakage problem at the transmitter side and leads to less interference from SUs to PUs and between the SUs in cognitive radio technology. The benefit of exploiting pulse shape filtering in the OFDM/OQAM is to not only eliminate the requirement of the guard bands but also reduce the out of band energy transmission, which also improves the spectral isolation from the neighboring systems. But the high PAPR phenomenon is a common issue in the majority of the multicarrier modulation systems thus OFDM/OQAM is no exception in this case.

scholarly journals A Novel Companding Technique to Reduce High Peak to Average Power Ratio in OFDM Systems

IEEE Access ◽  
2021 ◽  
Vol 9 ◽  
pp. 35217-35228
Author(s):  
Abdulwahid Mohammed ◽  
Tawfik Ismail ◽  
Amin Nassar ◽  
Hassan Mostafa
Keyword(s):  
Average Power ◽  
High Peak ◽  
Power Ratio ◽  
Ofdm Systems

scholarly journals Peak-to-average power ratio reduction based on Cross-Correlation in OFDM systems

2014 ◽  
Author(s):  
Mohsen Kazemian ◽  
Pooria Varahram ◽  
Shaiful Jahari B. Hashim ◽  
Borhanuddin B. Mohd. Ali ◽  
Somayeh Mohammady ◽  
...  
Keyword(s):  
Cross Correlation ◽  
Average Power ◽  
Power Ratio ◽  
Ofdm Systems ◽  
Power Ratio Reduction ◽  
Ratio Reduction
Sign in / Sign up

Export Citation Format

Share Document