Hand-off between ultra-wideband cell sites

Abstract

Briefly, the present invention provides a dynamic channel re-assignment capability between mobile units, base stations and sectors within base station coverage areas. The wireless devices used in the present invention may include ultra-wideband radio communication devices. Ultra-wideband bandwidth and channel allocation can be effectively managed, even though link quality generally deteriorates near the outer boundary of the base station. By maintaining dual communications with an adjoining base station, the present invention reduces the bit error rate and maintains signal strength.

1 . A method for performing a soft hand-off in an ultra-wideband code-based cellular communication system, wherein the soft hand-off is from a first mobile unit to a second mobile unit to a base station, the method comprising the steps of: 
 monitoring signal strength and the bit error rate from a first base station and determining that either is unacceptable;    attempting to locate an adjacent base station with an acceptable signal strength and bit error rate and determining that no adjacent base station has an acceptable signal strength and bit error rate;    transmitting a hand-off request from a first mobile device that is linked to the first base station to a second mobile device:    receiving; a response from the second mobile device: and using the second mobile device as a temporary repeater to pass data to a second base station.    
   
   
       2 . A computer program product for performing a soft hand-off in an ultra-wideband code-based cellular communication system, wherein the soft hand-off is from a first mobile unit to a second mobile unit to a base station, comprising: 
 computer code for monitoring signal strength and the bit error rate from a first base station and determining that either in unacceptable;    computer code for attempting to locate an adjacent base station with an acceptable signal strength and bit error rate and determining that no adjacent base station has an acceptable signal strength and bit error rate;    computer code for transmitting a hand-off request from a first mobile device that is linked to the first base station to a second mobile device;    computer code for receiving a response from the second mobile device; and    computer code for using the second mobile device as a temporary repeater to pass data to a second base station.    
   
   
       3 . A system for performing a soft hand-off in an ultra-wideband code-based cellular communication system, wherein the soft hand-off is from a first mobile unit to a second mobile unit to a base station, the system comprising: 
 means for monitoring signal strength and the bit error rate from a first base station and determining that either is unacceptable;    means for attempting to locate an adjacent base station with an acceptable signal strength and hit error rate and determining that no adjacent base station has an acceptable signal strength and bit error rate;    means for transmitting a hand-off request from a first mobile device that is linked to the first base station to a second mobile device;    means for receiving a response from the second mobile device; and    means for using the second mobile device as a temporary repeater to pass data to a second base station.    
   
   
       4 . A mobile unit for an ultra-wideband code-based cellular communication system, wherein mobile unit performs a soft hand-off to a second mobile unit to a base station, the mobile unit comprising: 
 means for monitoring signal strength and the bit error rate from a first base station to which it is linked sod determining that either is unacceptable;    means for attempting to locate an adjacent base station with an acceptable signal strength and bit error rate and determining that no adjacent base station has an acceptable signal strength and bit error rate;    means for transmitting a hand-off request to a second mobile device;    means for receiving a response from the second mobile device; and    means for using the second mobile device as a temporary repeater to pass data to a second base station.    
   
   
       5 . A base station system for an ultra-wideband code-based cellular communication system, wherein there is a soft hand-off from a first mobile unit to a second mobile unit to the base station, the base station comprising: 
 means for monitoring signal strength and the bit error rate from the first base station and determining that either is unacceptable; and    means for attempting to locate an adjacent base station with an acceptable signal strength and bit error rate and determining that no adjacent base station has an acceptable signal strength and bit error rate.