03-004: Cellular Network Handoff Modeling

Summary: This Mason Technology utilizes a new discrete-time framework for evaluating the performance of handoff mechanisms in 3G networks.

The handoff mechanism employed in a cellular network may have a significant impact on overall network performance. Evaluation of handoff mechanism performance has for the most part been carried out with brute-force computer simulation or simplified approximations. This invention utilizes a new discrete-time framework for evaluating the performance of handoff mechanisms in 3G networks. This recursive procedure is an efficient means for calculating cell handoff probabilities without the use of computer simulations and approximations. Using this approach, network performance measures such as outage probabilities, mean size of the active set, average signal loads, and macro diversity gain can be accurately calculated.

- Approximations and time consuming computer simulations are avoided
- Optimizes network resources and contributes to more efficient design
- Performance measures computed verses imputed
- Accurate calculation of signaling loads
- Network upgrade analysis and timing improved
- Improved network quality

Market Significance:
A long-standing challenge in the wireless industry is efficient design of handoff mechanisms for wireless networks. If properly designed, a mobile user should not experience call impairments such as lost calls or fading. Currently, this is not an exact science and is based on time-consuming computer simulations and approximations in a dynamic environment. As a result, users will experience service that is not equivalent to wire-line quality. This inconsistency continues to erode customer confidence in network reliability and their dependence on wireless services at their primary means of voice and data transfer. The discrete-time analysis of a soft handoff algorithm developed at George Mason University addresses design of handoff mechanisms and subsequent evaluation of handoff performance in cellular networks. It should not be overlooked that precise performance measurements for a mobile unit may provide an opportunity for wireless carriers to consider network based service level agreements. By implementing a discrete algorithm the following benefits are anticipated.

- Potential cost savings derived from increased network efficiency
- Improved service yields lower customer churn and better service for your customers
- Lower potential for service interruption equates to lower incidence of account reimbursements
- Potential network based service level agreement