CONCLUSIONS

Throughout this study, and based partially on interactions with selected U.S., European, and Japanese companies, it is recognized that there is substantial need for systems research for future wireless applications. The following research areas are either emerging or evolving and are considered important for future health of wireless communication systems:

• new decoding algorithms for turbo codes for wireless channels
• new coding/modulation techniques for reducing the peak-to-mean envelope ratio, maximizing the data rate and providing large coding gain
• new approaches to jointly designing modulation techniques, and power amplifiers to simultaneously obtain high power added efficiency along with bandwidth efficiency
• new demodulation/decoding techniques to simultaneously combat the near-far problem and do channel decoding in multi-rate DS-CDMA systems
• communication problems unique to high frequency systems (e.g., channel estimation)
• joint channel estimation and decoding/demodulation algorithms
• multiple-access techniques for multi-rate systems with variable quality of service requirements
• space-time coding for systems with multiple antennas
• analog decoding techniques for high speed, low power systems
• ultra wideband systems and hardware design
• research in methodologies for an integrated approach to wireless communications (device layer: e.g., power and low noise amplifiers, mixers, filters; physical layer: coding, modulation; medium access layer: CDMA/FDMA/TDMA; data link layer: hybrid ARQ; network layer: routing protocols)