TY - JOUR
T1 - Locally optimal soft handoff algorithms
AU - Prakash, Rajat
AU - Veeravalli, Venugopal V.
N1 - Funding Information:
Manuscript received June 13, 2001; revised April 5, 2002. This work was supported in part by the Office of Naval Research under Grant N0014-97-1-0823 and by Nortel Networks’ Global External Research (both through Cornell University) and by the National Science Foundation CAREER/PECASE under Grant CCR-0049089 (through the University of Illinois). This work was presented in part at the Vehicular Technology Conference 2000, Tokyo, Japan, May 2000.
PY - 2003/3
Y1 - 2003/3
N2 - The design of soft handoff algorithms for cellular radio systems is considered. The design problem is posed as a tradeoff between three metrics: the rate of handoffs, the mean size of the active set, and the link quality. It is argued that the algorithm that optimizes the tradeoff between these metrics is impractical. Hence, a locally optimal (LO) handoff algorithm is derived as a practical approximation to the optimal handoff algorithm. The LO algorithm is shown to yield a significantly better tradeoff than the static threshold handoff algorithm used in second-generation code-division multiple-access (CDMA) systems. It is also shown that the dynamic threshold algorithm, which is an ad hoc algorithm proposed for third-generation CDMA systems, achieves nearly the same performance as the LO algorithm. Thus, an analytical justification is developed for the dynamic threshold algorithm. Further, handoff algorithm design is separated into independent design problems on the forward and reverse links. The forward link LO algorithm is shown to be computationally intensive but is also shown to be closely approximated by the simpler reverse link LO algorithm.
AB - The design of soft handoff algorithms for cellular radio systems is considered. The design problem is posed as a tradeoff between three metrics: the rate of handoffs, the mean size of the active set, and the link quality. It is argued that the algorithm that optimizes the tradeoff between these metrics is impractical. Hence, a locally optimal (LO) handoff algorithm is derived as a practical approximation to the optimal handoff algorithm. The LO algorithm is shown to yield a significantly better tradeoff than the static threshold handoff algorithm used in second-generation code-division multiple-access (CDMA) systems. It is also shown that the dynamic threshold algorithm, which is an ad hoc algorithm proposed for third-generation CDMA systems, achieves nearly the same performance as the LO algorithm. Thus, an analytical justification is developed for the dynamic threshold algorithm. Further, handoff algorithm design is separated into independent design problems on the forward and reverse links. The forward link LO algorithm is shown to be computationally intensive but is also shown to be closely approximated by the simpler reverse link LO algorithm.
KW - Cellular systems
KW - Code-division multiple access (CDMA)
KW - Handover
UR - http://www.scopus.com/inward/record.url?scp=0038291821&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0038291821&partnerID=8YFLogxK
U2 - 10.1109/TVT.2003.808810
DO - 10.1109/TVT.2003.808810
M3 - Article
AN - SCOPUS:0038291821
VL - 52
SP - 347
EP - 356
JO - IEEE Transactions on Vehicular Communications
JF - IEEE Transactions on Vehicular Communications
SN - 0018-9545
IS - 2
ER -