Title :
Clip correction in wireless LAN receivers
Author :
Rietman, Ronald ; Linnartz, Jean-Paul ; De Vries, Eric Penning
Author_Institution :
Philips Res. Labs., Eindhoven
Abstract :
OFDM signals suffer from a large peak to average power ratio, which requires large power back-offs in the transmit and receive chains. This paper presents a digital postprocessing method that mitigates clipping by the analog-to-digital converter (ADC) in the receiver. Clipped peaks cause spurious signals on empty subcarriers, which can be used to eliminate clipping artifacts and to recover the original signal. Simulations show that a significant reduction of 3 dB in the headroom of the A/D converter (ADC) is possible, when an elaborate MMSE clip correction algorithm is used. A simple algorithm still allows for 1 dB reduction of the headroom. As the ADC is consuming an ever increasing fraction of the total receiver power, the results are believed to be relevant for low-power design of OFDM receivers, for instance to prolong battery life of laptops and other portable WLAN devices.
Keywords :
OFDM modulation; analogue-digital conversion; least mean squares methods; radio receivers; wireless LAN; A-D converter; ADC; MMSE clip correction algorithm; OFDM receivers; OFDM signals; analog-to-digital converter; digital postprocessing method; laptops; minimum mean square error methods; peak-to-average power ratio; portable WLAN devices; wireless LAN receivers; Analog-digital conversion; Baseband; Batteries; Energy consumption; Laboratories; OFDM; Peak to average power ratio; Signal processing algorithms; Transmitters; Wireless LAN;
Conference_Titel :
Wireless Technology, 2008. EuWiT 2008. European Conference on
Conference_Location :
Amsterdam
Print_ISBN :
978-2-87487-008-8