Interference resistant scalable video transmission over DS-CDMA channels

Abstract

In this work, we demonstrate the interference mitigation capabilities of the auxiliary vector (AV) receiver for scalable video transmission over direct-sequence code division multiple access (DS-CDMA) systems using a hardware testbed. The proposed receiver design is also compared to the conventional RAKE matched-filter (RAKE-MF) and minimum variance distortionless response (MVDR) receivers. The DS-CDMA video data stream is transmitted over an RF channel under “real world” Rayleigh-faded multipath channel conditions, emulating open and/or urban battlefield environments. The state-of-the-art Agilent E4438C Vector Signal Generator and Baseband Studio Fader is used to provide a configurable “real time” RF channel. In this work, the “foreman” video sequence is source encoded using an MPEG-4 compatible video codec and channelcoded using rate-compatible punctured convolutional (RCPC) codes. After spreading and modulating, the resultant bitstream is transmitted over a user-defined Agilent wireless channel emulation. Upon chip-matched filtering and sampling at the chip-rate on a hardware testbed, the received data are despread/demodulated using the AV, RAKE-MF and MVDR receivers and, subsequently, channel and source decoded. The resultant video clips exemplify that the AV receiver outperforms the MVDR and the RAKE-MF receiver counterparts under a wide range of rates and channel conditions.