Method and apparatus for controlling transmission power in a CDMA cellular mobile telephone system

An apparatus for controlling transmission signal power in a cellular mobile telephone in communications having a plurality of cell-site stations using code division multiple access (CDMA) spread spectrum communication signals, said cellular mobile telephone having an antenna coupled to a transmitter and a receiver, said transmitter for generating and transmitting a CDMA carrier signal according to an assigned spreading function modulated by a mobile user input information signal, said receiver for receiving CDMA communication signals from at least two of said cell-site stations and spread spectrum processing said received CDMA communication signals according to an assigned spreading function so as to recover a mobile user output information signal intended for a user of said cellular mobile telephone, said at least two cell-site stations communicating power control commands in CDMA communication signals intended for said cellular mobile telephone with said receiver providing an output of said power control commands, said apparatus comprising:

• measurement means for, operatively coupling to said receiver, measuring combined signal power in contemporaneously received CDMA communication signals and providing a measurement signal indicative of measured signal power;
• adjustment means for, operatively coupling to said transmitter, receiving said measurement signal, varying transmitter signal power in opposite correspondence to variations in measured signal power about a predetermined power level;
• and
• additional adjustment means for, operatively coupling to said receiver and transmitter, receiving said power adjustment commands, decreasing transmitter signal power when at least one of said at least two cell-site station transmitted power adjustment commands as received at said receiver is indicative of a decrease in transmitter signal power, and for increasing transmitter signal power when all of said at least two cell-site transmitted power adjustment commands as received at said receiver are indicative of an increase in transmitter signal power.

In a cellular mobile telephone system in which system users communicate information signals between one another via at least one cell-site using code division multiple access (CDMA) spread spectrum communication signals, a method for controlling transmission signal power of a mobile telephone in said cellular mobile telephone system, wherein said mobile telephone has an antenna, transmitter and receiver, and each cell-site has an antenna, at least one transmitter and at least one receiver, and said mobile telephone communicates CDMA communication signals with at least two of said cell-sites, said method comprising the steps of:

• measuring signal power in CDMA communication signals received by said mobile telephone receiver;
• varying transmission signal power of each corresponding mobile telephone transmitter in opposite correspondence to variations in corresponding mobile telephone power measurements with respect to a first predetermined power level;
• measuring signal power in each CDMA communication signal received at said at least two cell-site receivers as transmitted from said mobile telephone transmitter;
• generating power adjustment commands corresponding to deviations in said at least two cell-site power measurements from a second predetermined power level, wherein said power adjustment commands are indicative of a request for at an increase in mobile telephone transmitter power when each said respective cell-site measured power is below said second power level and indicative of a decrease in mobile telephone transmitter power when each said respective cell-site measured power is above said second power level;
• transmitting by said at least two cell-sites said respective power adjustment commands along with said information signals to said mobile telephone;
• receiving at each respective mobile telephone receiver said power adjustment commands corresponding thereto;
• decreasing transmission signal power of said mobile telephone transmitter when said power adjustment commands as as transmitted by at least one of said at least two cell-site and received at said mobile telephone receiver system is indicative of a decrease in transmission signal power of said mobile telephone transmitter;
• and
• increasing transmission signal power of said mobile telephone transmitter when said transmitted power adjustment commands as transmitted by all of said at least two cell-site and received at said mobile telephone receiver system are indicative of an increase in transmission signal power of said mobile telephone transmitter.

A method for controlling transmission signal power in a cellular mobile telephone in communications with at least two cell-site station using code division multiple access (CDMA) spread spectrum communication signals, said cellular mobile telephone having an antenna coupled to a transmitter and a receiver, said transmitter for generating and transmitting a CDMA carrier signal according to an assigned spreading function modulated by a mobile user input information signal, said receiver for receiving CDMA communication signals from at least two of said cell-site stations and spread spectrum processing said received CDMA communication signals according to an assigned spreading function to recover a mobile user output information signal intended for a user of said cellular mobile telephone, said from at least two of said cell-site stations communicating power control commands in CDMA communication signals intended for said cellular mobile telephone with said receiver processing said received power control commands and providing an output of said power control commands, said method comprising the steps of:

• measuring combined signal power in contemporaneously received CDMA communication signals;
• varying transmitter signal power in opposite correspondence to variations in measured signal power about a predetermined power level;
• and
• varying transmitter signal power in correspondence to received power adjustment commands by, decreasing transmitter signal power when at least one of said at least two cell-site station transmitted power adjustment commands as received at said receiver is indicative of a decrease in transmitter signal power, and increasing transmitter signal power when all of said at least two cell-site transmitted power adjustment commands as received at said receiver are indicative of an increase in transmitter signal power.