Dynamic bandwidth allocation for multimedia traffic with rate guarantee and fair access in WCDMA systems

ABSTRACT

Packet scheduling in a WCDMA system poses a new challenge due to its nature of variable bit rates and location-dependent, time-varying channel conditions. In this work, two new downlink scheduling algorithms for a WCDMA base station are proposed to support multimedia transmissions. With a credit management and a compensation mechanism, our algorithms provide rate guarantee and fair access to the channel. In particular, we propose to allow a user to simultaneously use multiple OVSF codes in a time-sharing manner. Using multiple codes allows us to compensate those users suffering from communication interferences or even errors. Simulation results are presented to verify that the proposed schemes do achieve higher bandwidth utilization while keeping transmission delay low.

REFERENCES

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INDEX TERMS

Primary Classification:
  C. Computer Systems Organization
  C.2 COMPUTER-COMMUNICATION NETWORKS
      C.2.1 Network Architecture and Design
          Subjects: Wireless communication

General Terms:
Algorithms, Design, Management, Performance

Keywords:
3G, OVSF, WCDMA, mobile computing, personal communication services, wireless communication