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http://dx.doi.org/10.17661/jkiiect.2020.13.1.42

Memory Reduction Method of Radix-22 MDF IFFT for OFDM Communication Systems  

Cho, Kyung-Ju (Department of Electronic Engineering Wonkwang University)
Publication Information
The Journal of Korea Institute of Information, Electronics, and Communication Technology / v.13, no.1, 2020 , pp. 42-47 More about this Journal
Abstract
In OFDM-based very high-speed communication systems, FFT/IFFT processor should have several properties of low-area and low-power consumption as well as high throughput and low processing latency. Thus, radix-2k MDF (multipath delay feedback) architectures by adopting pipeline and parallel processing are suitable. In MDF architecture, the feedback memory which increases in proportion to the input signal word-length has a large area and power consumption. This paper presents a feedback memory size reduction method of radix-22 MDF IFFT processor for OFDM applications. The proposed method focuses on reducing the feedback memory size in the first two stages of MDF architectures since the first two stages occupy about 75% of the total feedback memory. In OFDM transmissions, IFFT input signals are composed of modulated data and pilot, null signals. In order to reduce the IFFT input word-length, the integer mapping which generates mapped data composed of two signed integer corresponding to modulated data and pilot/null signals is proposed. By simulation, it is shown that the proposed method has achieved a feedback memory reduction up to 39% compared to conventional approach.
Keywords
Feedback memory size reduction; IFFT; Multipath delay feedback (MDF); Parallel; Pipeline;
Citations & Related Records
Times Cited By KSCI : 4  (Citation Analysis)
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