Title :
Use of a Variable Wordlength Technique in an OFDM Receiver to Reduce Energy Dissipation
Author :
Yoshizawa, Shingo ; Miyanaga, Yoshikazu
Author_Institution :
Grad. Sch. of Inf. Sci. & Technol., Hokkaido Univ., Sapporo
Abstract :
Wordlength determination is an indispensable task in digital hardware implementations of signal processing algorithms because the wordlength affects power consumption and system performance. There is a tradeoff between power consumption and system performance when searching for the optimum wordlength. We have developed a technique of dynamically controlling the wordlength used in the signal processing algorithms of wireless orthogonal frequency-division multiplexing (OFDM) receivers. The receiver dynamically changes the wordlength on the basis of the conditions in the propagation environment while satisfying the user-required communication quality. That is, the system optimizes the wordlength while operating by sensing its own performance and gradually adjusting this wordlength to improve performance. Testing revealed that, for a packet error rate (PER) of 10-2 , the application of this technique to an OFDM receiver reduces energy dissipation by 18.1%-30.2%.
Keywords :
OFDM modulation; error statistics; radio receivers; signal processing; OFDM receiver; energy dissipation; packet error rate; power consumption; signal processing algorithms; variable wordlength technique; wireless orthogonal frequency-division multiplexing receivers; Low power; OFDM; VLSI architecture; low power; orthogonal frequency-division multiplexing (OFDM); receiver; variable wordlength; wireless communication;
Journal_Title :
Circuits and Systems I: Regular Papers, IEEE Transactions on
DOI :
10.1109/TCSI.2008.920098