Digital Finite Impulse Response Equalizer for Nonlinear Frequency Response Compensation in Wireless Communication
Signal distortion can occur when the gain or attenuation of a component changes non-linearly with frequency, which is referred to as nonlinear frequency response. Common communications components such as filters, amplifiers, and mixers can lead to nonlinear frequency responses, which can cause error...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-04-01
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| Series: | Electronics |
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| Online Access: | https://www.mdpi.com/2079-9292/12/9/2010 |
| _version_ | 1797602789768036352 |
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| author | Zhenyu Zhang Yanan Li Bassam Nima |
| author_facet | Zhenyu Zhang Yanan Li Bassam Nima |
| author_sort | Zhenyu Zhang |
| collection | DOAJ |
| description | Signal distortion can occur when the gain or attenuation of a component changes non-linearly with frequency, which is referred to as nonlinear frequency response. Common communications components such as filters, amplifiers, and mixers can lead to nonlinear frequency responses, which can cause errors in transmitting and receiving. This article outlines the design and demonstration of a static and dynamic finite impulse response (FIR) digital equalizer circuit. Using predistortion topology with a coupled feedback loop, the adaptive Least-Mean Square (LMS) algorithm was implemented. The FIR filter was simulated in MATLAB and Vivado and then implemented onto an Eclypse Z7 Field Programmable Gate Array (FPGA) evaluation board. Simulations showed that the custom RTL module gave the same frequency response that was produced in MATLAB calculations. The filter was able to dynamically equalize the frequency responses of different nonlinear boards that were used as the devices under test (DUT). Measurements showed that the equalizer was able to compensate for system distortion from 0.2 to 0.8 Nyquist frequency. The phase response remained relatively linear across the band of interest, with a group delay flatness less than 10 ns. |
| first_indexed | 2024-03-11T04:21:27Z |
| format | Article |
| id | doaj.art-baa3fb6bee48449cb151cebd40da893e |
| institution | Directory Open Access Journal |
| issn | 2079-9292 |
| language | English |
| last_indexed | 2024-03-11T04:21:27Z |
| publishDate | 2023-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Electronics |
| spelling | doaj.art-baa3fb6bee48449cb151cebd40da893e2023-11-17T22:47:29ZengMDPI AGElectronics2079-92922023-04-01129201010.3390/electronics12092010Digital Finite Impulse Response Equalizer for Nonlinear Frequency Response Compensation in Wireless CommunicationZhenyu Zhang0Yanan Li1Bassam Nima2Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB T6G 2R3, CanadaDepartment of Electronics and Information Engineering, Beijing-Dublin International College, Beijing University of Technology, Beijing 100022, ChinaDepartment of Electrical and Computer Engineering, University of Alberta, Edmonton, AB T6G 2R3, CanadaSignal distortion can occur when the gain or attenuation of a component changes non-linearly with frequency, which is referred to as nonlinear frequency response. Common communications components such as filters, amplifiers, and mixers can lead to nonlinear frequency responses, which can cause errors in transmitting and receiving. This article outlines the design and demonstration of a static and dynamic finite impulse response (FIR) digital equalizer circuit. Using predistortion topology with a coupled feedback loop, the adaptive Least-Mean Square (LMS) algorithm was implemented. The FIR filter was simulated in MATLAB and Vivado and then implemented onto an Eclypse Z7 Field Programmable Gate Array (FPGA) evaluation board. Simulations showed that the custom RTL module gave the same frequency response that was produced in MATLAB calculations. The filter was able to dynamically equalize the frequency responses of different nonlinear boards that were used as the devices under test (DUT). Measurements showed that the equalizer was able to compensate for system distortion from 0.2 to 0.8 Nyquist frequency. The phase response remained relatively linear across the band of interest, with a group delay flatness less than 10 ns.https://www.mdpi.com/2079-9292/12/9/2010nonlinear frequency responseradio frequency (RF)wireless communicationpredistortiondigital equalizerfinite impulse response (FIR) filter |
| spellingShingle | Zhenyu Zhang Yanan Li Bassam Nima Digital Finite Impulse Response Equalizer for Nonlinear Frequency Response Compensation in Wireless Communication Electronics nonlinear frequency response radio frequency (RF) wireless communication predistortion digital equalizer finite impulse response (FIR) filter |
| title | Digital Finite Impulse Response Equalizer for Nonlinear Frequency Response Compensation in Wireless Communication |
| title_full | Digital Finite Impulse Response Equalizer for Nonlinear Frequency Response Compensation in Wireless Communication |
| title_fullStr | Digital Finite Impulse Response Equalizer for Nonlinear Frequency Response Compensation in Wireless Communication |
| title_full_unstemmed | Digital Finite Impulse Response Equalizer for Nonlinear Frequency Response Compensation in Wireless Communication |
| title_short | Digital Finite Impulse Response Equalizer for Nonlinear Frequency Response Compensation in Wireless Communication |
| title_sort | digital finite impulse response equalizer for nonlinear frequency response compensation in wireless communication |
| topic | nonlinear frequency response radio frequency (RF) wireless communication predistortion digital equalizer finite impulse response (FIR) filter |
| url | https://www.mdpi.com/2079-9292/12/9/2010 |
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