Study of air interface techniques for wireless LANs

There have been many different techniques developed to combat the ISI problem. Among them are adaptive equalization, CDMA, various multicarrier schemes and the use of intelligent antennas with diversity and directivity. For the HIPERLAN application, adaptive equalization and multicarrier schemes appear attractive. This paper reports a study of the two techniques, emphasising the critical issues relating to each approach, i.e., RF front-end linearity requirements for multicarrier schemes and base-band processing techniques for equalisation schemes