Transmit EVM Improvement of OFDM based Wireless LAN through Rescaling and Block Floating Point IFFT Implementation

Performance of wireless transceivers for high throughput and long range applications depends on several important factors such as transmit power, antenna configuration, and link quality and residual TX-RF impairments induced inside the TX/RX unit itself and most importantly on the chosen waveform. This paper proposes baseband architecture and methods to reduce residual TX-RF impairments. In particular, we focus on representation of I and Q samples of IFFT output. A prototype of customized 802.11g transmitter in 10MHz bandwidth was designed and tested this method for reduced EVM.