Detection Schemes for High Order M-Ary QAM Under Transmit Nonlinearities

Date

2019-07-01

Author

Gulgun, Ziya
Yılmaz, Ali Özgür

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

129
views

0
downloads

Nonlinearities in various stages of a transmitter may hinder and restrict the transmission rate. As observed in many studies, outermost constellation points are usually more adversely affected by these impairments. To observe these effects, we utilize two power amplifier models that have different effects on transmitted signals. The Rapp model considers only amplitude deformation and the resultant in-phase and quadrature errors can be assumed to be independent on the receiver side. Unlike the Rapp model, the Saleh model exerts both amplitude and phase deformations and the phase deformation introduces correlation between the in-phase and quadrature errors according to our observations. In addition to the correlation, the variances of in-phase and quadrature errors may not be equal to each other. In this paper, we propose receivers that consider error variances of each quadrature amplitude modulation (QAM) symbol. We compare the performances of the receivers with those of other receivers that take average error variances into account for decoding. Furthermore, we propose a practical receiver that directly works on digitized observations based on a look-up table that keeps log-likelihood ratios of the quantized regions in order to reduce computational complexity.

Subject Keywords

Electrical and Electronic Engineering

URI

https://hdl.handle.net/11511/44921

Journal

IEEE TRANSACTIONS ON COMMUNICATIONS

DOI

https://doi.org/10.1109/tcomm.2019.2905569

Collections

Department of Electrical and Electronics Engineering, Article

Suggestions

OpenMETU
Core

Design of Maisel sidelobe blankers with a guarantee on the gap to optimality COŞKUN, Osman; Candan, Çağatay (Institution of Engineering and Technology (IET), 2016-11-01) The conventional sidelobe blanking system, known as the Maisel sidelobe blanker, uses two receiving channels with different gains to detect the presence of a jammer. The Maisel system is an ad-hoc detector without any optimality properties. Yet, it has been successfully utilised in numerous operational systems. Here, the authors study the optimum Neyman-Pearson type sidelobe blanking (SLB) detectors for the Swerling target models to assist the design of Maisel blankers. The authors note that the optimal sid...
Unity power factor boost converter with phase shifted parallel IGBT operation for medium power applications Cadirci, I; Yafavi, A; Ermiş, Muammer (Institution of Engineering and Technology (IET), 2002-05-01) Phase-shifted parallel (PSP) operation of IGBTs is proposed for unity pf boost converters, to increase both the converter power rating and operating frequency. This technique allows unity pf operation of medium power AC and DC motor drives, and switch mode power supplies from a single-phase, unregulated AC supply, with minimum line current harmonic distortion. Since operating frequency is increased by integer multiples of IGBT switching frequency, the same core size for the boost inductor can be used to tra...
Joint spatial and temporal channel-shortening techniques for frequency selective fading MIMO channels Toker, Canan; Chambers, JA; Baykal, Buyurman (2005-02-01) It is well understood that the maximum likelihood estimator is a powerful equalisation technique for frequency selective fading channels, and in particular for MIMO systems. The complexity of this estimator, however, grows exponentially with the number of users and multipath taps, hence limiting the use of this algorithm in MIMO systems. In the paper, the authors propose a joint spatial and temporal channel-shortening filter as a pre-processor to reduce significantly the complexity of a maximum likelihood e...
Design and implementation of low phase noise phase locked loop based local oscillator Bölücek, Muhsin Alperen; Yıldırım, Nevzat; Department of Electrical and Electronics Engineering (2009) In this thesis, a low phase noise local oscillator operating at 2210 MHz is designed and implemented to be used in X-Band transmitter of a LEO satellite. Designed local oscillator is a PLL (Phase Locked Loop) based frequency synthesizer which is implemented using discrete commercial components including ultra low noise voltage controlled oscillator and high resolution, low noise fractional-N synthesizer. Operational settings of the synthesizer are done using three wire serial interface of a microcontroller....
Performance Enhancement of the Single-Phase Series Active Filter by Employing the Load Voltage Waveform Reconstruction and Line Current Sampling Delay Reduction Methods Senturk, Osman S.; Hava, Ahmet Masum (Institute of Electrical and Electronics Engineers (IEEE), 2011-08-01) This paper proposes the waveform reconstruction method (WRM), which is utilized in the single-phase series active filter's (SAF's) control algorithm, in order to extract the load harmonic voltage component of voltage harmonic type single-phase diode rectifier loads. Employing WRM and the line current sampling delay reduction method, a single-phase SAF compensated system provides higher harmonic isolation performance and higher stability margins compared to the system using conventional synchronous-reference...

Citation Formats

Z. Gulgun and A. Ö. Yılmaz, “Detection Schemes for High Order M-Ary QAM Under Transmit Nonlinearities,” IEEE TRANSACTIONS ON COMMUNICATIONS, pp. 4825–4834, 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/44921.