From WiFi to WiMAX: Techniques for High-Level IP Reuse across Different OFDM Protocols

Abstract

Orthogonal frequency-division multiplexing (OFDM) has become the preferred modulation scheme for both broadband and high bitrate digital wireless protocols because of its spectral efficiency and robustness against multipath interference. Although the components and overall structure of different OFDM protocols are functionally similar, the characteristics of the environment for which a wireless protocol is designed often result in different instantiations of various components. In this paper, we describe how we can instantiate baseband processoring of two different wireless protocols, namely 802.11a and 802.16 in Bluespec from a highly parameterized code for a generic OFDM protocol. Our approach results in highly reusable IP blocks that can dramatically reduce the time-to-market of new OFDM protocols. One advantage of Bluespec over SystemC is that our code is synthesizable into high quality hardware, which we demonstrate via synthesis results. Using a Viterbi decoder we also demonstrate how parameterization can be used to study area-performance tradeoff in the implementation of a module. Furthermore, parameterized modules and modular composition can facilitate implementation-grounded algorithmic exploration in the design of new protocols.