Digital Compensation for Analog Front-Ends: A New Approach to Wireless Transceiver Design

6

Emerging Wireless Communication Systems

At the beginning of the book, we introduced the air interfaces emerging in the new communication systems and evaluated their performance. We presented the possible analog front-end architectures and highlighted different sources of possible non-ideality. The degradation caused by the non-ideal front-end on the performance of the communication systems was also assessed. A generic approach to compensate numerically for the front-end non-ideality was developed. It is composed of two distinct phases:

• the acquisition, taking care of the rough estimation/compensation of the effects and relying on a preamble sent at the beginning of the burst;
• the tracking, taking care of the fine estimation/compensation of the effects and relying on pilot symbols interleaved in the data symbols.

In this final chapter, we show that the methodology developed to cope with the non-ideal front-end can be extended and applied to the most recent communication systems. We will successively address the IEEE 802.11n WLAN MIMO communication system (Section 6.1) and the 3GPP LTE multi-user cellular communication system (Section 6.2). Our goal is not to solve the problem completely for each emerging communication system, but rather to address the most challenging issues resulting from the particular configuration of each system. For each system, we will present the status of the standard and the targeted objectives, we will describe the burst organization (location of ...