Telecommunications – Radiotelephone system – Zoned or cellular telephone system
Patent
1997-02-18
1999-12-07
Urban, Edward F.
Telecommunications
Radiotelephone system
Zoned or cellular telephone system
455436, 455439, 455440, H04Q 700
Patent
active
059998164
ABSTRACT:
A method and apparatus for performing inter-system hard handoff between communication systems or inter-frequency hard handoff within a CDMA communication system is disclosed. The purpose of this invention is to reduce the probability of dropped calls during inter-system hard handoff. In the event that a hard handoff attempt is unsuccessful, the mobile station will return to the original system with information which the communication system of the present invention uses to assist in the performance of future handoff attempts. Alternatively, with no handoff attempt made, the mobile station monitors the destination system then returns to the original system with information used to assist in subsequent handoff attempts. The information returned from monitoring a CDMA system consists of results of a search for one or more pilots given at offsets in a specific list provided to the mobile station by the base station or a set of offsets based upon a predetermined search algorithm.
REFERENCES:
patent: 4901307 (1990-02-01), Gilhousen et al.
patent: 5101501 (1992-03-01), Gilhousen et al.
patent: 5239676 (1993-08-01), Strawczynski et al.
patent: 5267261 (1993-11-01), Blakeney, II et al.
patent: 5295153 (1994-03-01), Gudmundson
patent: 5590177 (1996-12-01), Vilmur et al.
patent: 5594718 (1997-01-01), Weaver, Jr. et al.
patent: 5634192 (1997-05-01), Meche et al.
patent: 5649000 (1997-07-01), Lee et al.
patent: 5666356 (1997-09-01), Flenning et al.
patent: 5682380 (1997-10-01), Park et al.
patent: 5722072 (1998-02-01), Chrichton et al.
patent: 5737704 (1998-04-01), Jin et al.
patent: 5848063 (1998-12-01), Weaver et al.
"Soft Handoff frame format" by Edward Tiedemann, TIA Document, Dec. 11-14, 1995, pp. 1-7.
"Alternative methods for Inter-Channel Handoff" by Charles Wheatley, TIA Document; pp. 1-3, Nov. 10-20, 1992.
"Proposed Draft Liaison Statement to TR.45.2" by Edward G. Tiedemann, Jr. TIA Document, pp. 1-32; Dec. 3-11, 1992.
"Intersystem Issues for Support of the Wideband Spread-Spectrum Digital Standard" by Gadi Karmi, TIA Document; Oct. 6, 1992, pp. 1-7.
"Cellular Radiotelecommunications Intersystem Operations: Authentication, Signaling Message Encryption and Voice Privacy" TIA/EIA Telecommunications Systems Bulletin, May 1993.
"Cellular Radiotelelcommunications Intersystem Operations: Intersystem Handoff" EIA/TIA Interim Standard, Dec. 1991.
"IS-41-B Mobile Border System Problems" TIA/EIA Telecommunications Systems Bulletin, Apr. 1994.
"IS-41-B Support for Dual-Mode Wideband Spread Spectrum Mobile Stations" TIA/EIA Telecommunications Systems Bulletin, Jan. 1994.
TIA document "CDMA Intersystem Operations" by Alejandro Holcman et al. Presented at IEEE Conference on Vehicular Technology committee, Stockholm, Sweden, Jun. 8, 1994.
TIA TR45.2 Intersystems Operations Presentation "The Wideband Spread Spectrum Standard Under Development in TR45.5" by Edward G. Tiedemann, presented din Atlanta, GA Nov. 16-20 1992.
TIA document "Intersystem Operation With The Proposed Wideband Spread Spectrum Dual-Mode Station-Base Station Compatibility Standard" by Gadi Karmi et al. presented May 1992 in Atlanta, GA.
Chen Tao
Tiedemann Jr. Edward G.
Baker Kent D.
Greenhaus Bruce W.
Miller Russell B.
Nguyen Thuan T.
Qualcomm Incorporated
LandOfFree
Method and apparatus for performing mobile assisted hard handoff does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for performing mobile assisted hard handoff, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for performing mobile assisted hard handoff will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-835041