Impact of cooperative space–time/frequency diversity in OFDM-based wireless sensor systems over mobile multipath channels

• Published in: IET wireless sensor systems Vol. 6; no. 4; pp. 138 - 143
• Main Authors: Zhang, Jiayi, Gharavi, Hamid, Hu, Bin
• Format: Journal Article
• Language: English
• Published: England The Institution of Engineering and Technology 01.08.2016
• Subjects: channel coding; channel Doppler spreads; Channels; cooperative communication; cooperative LDC‐aided ST‐SF‐OFDM; cooperative linear dispersion coding; cooperative source nodes; cooperative space‐time‐frequency diversity; Delay; delay spread; destination nodes; diversity reception; Doppler; Doppler effect; fading channels; frequency‐tones; Gain; linear codes; MIMO communication; mobile multipath channels; multipath channels; OFDM modulation; OFDM‐based wireless sensor systems; Orthogonal Frequency Division Multiplexing; Regular Papers; Sensors; spatial diversity; Spreads; ST‐SF diversity gains; time‐frequency‐selective fading channels; time‐slots; virtual multiinput‐multioutput systems; wireless sensor networks; wireless sensor networks; linear codes; orthogonal frequency division multiplexing; channel coding; channel Doppler spreads; ST-SF diversity gains; time-frequency-selective fading channels; fading channels; cooperative LDC-aided ST-SF-OFDM; OFDM modulation; MIMO communication; diversity reception; cooperative linear dispersion coding; destination nodes; mobile multipath channels; frequency-tones; multipath channels; time-slots; delay spread; cooperative communication; virtual multiinput-multioutput systems; cooperative space-time-frequency diversity; spatial diversity; cooperative source nodes; OFDM-based wireless sensor systems
• ISSN: 2043-6386; 2043-6394; 2043-6394
• DOI: 10.1049/iet-wss.2015.0033

Cooperative linear dispersion coding (LDC) can support arbitrary configurations of source nodes and destination nodes in virtual multi-input–multi-output systems. In this study, the authors investigate two spatial diversity applications of cooperative LDC for orthogonal frequency division multiplexing (OFDM)-based wireless sensor systems in order to achieve space–time/frequency (ST/SF) diversity gains when transmitting over time-/frequency-selective fading channels. Cooperative LDC-aided ST-/SF-OFDM is flexible in configuring various numbers of cooperative source nodes and time-slots or frequency-tones. Their results show that the ST-OFDM scheme is sensitive to exploiting diversity gains, subject to the impact of varying channel Doppler spreads; while the performance of SF-OFDM is mainly subject to delay spread. Specifically, when the system involves more than two cooperative nodes, the cooperative LDC-aided ST-/SF-OFDM outperforms the cooperative orthogonal block codes (e.g. Tarokh's codes) aided ST-/SF-OFDM, when communicating over a higher Doppler/delay spread.