Subblock processing in MMSE-FDE under fast fading environments

• Published in: IEEE journal on selected areas in communications Vol. 26; no. 2; pp. 359 - 365
• Main Authors: Kambara, K., Nishimoto, H., Nishimura, T., Ohgane, T., Ogawa, Y.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-02-2008; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Blocking; Channels; Degradation; Equalization; Error analysis; Fading; Frequency domain analysis; Frequency domains; Intersymbol interference; Numerical analysis; OFDM; Peak to average power ratio; Size control; Standardization; Terminals; WiMAX
• ISSN: 0733-8716; 1558-0008
• DOI: 10.1109/JSAC.2008.080212

Frequency domain equalization (FDE) has been studied for reducing inter-symbol interference (ISI) caused by frequency selective fading in single carrier systems. When a high-mobility terminal exists in the system, the channel state may change within a DFT block. Then, the ISI reduction performance of FDE degrades since cyclicity of the channel matrix is lost. We propose to divide a received data block into multiple subblocks to decrease the channel transition within the DFT block in fast fading environments. Also, to satisfy periodicity of the received signal in each subblock, we introduce a pseudo cyclic prefix technique. The results of numerical analysis show that the proposed method can effectively decrease the error floor in fast fading environments.