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

In a digital cellular communication system in which a remote user and another user communicate information signals to one another via a relay station using spread spectrum modulated signals in the relay of said information signals between said relay station and said remote user, a system for controlling transmission power in said relay station transmitted spread spectrum signal comprising:

• a relay station for spread spectrum modulating and transmitting a first information signal as a first spread spectrum signal at a first predetermined transmission level;
• a remote user communication station for receiving and demodulating said first spread spectrum signal to recover said first information signal, generating power adjustment information indicative of signal quality of said first information signal, and spread spectrum modulating and transmitting said power adjustment information to said relay station in a second spread spectrum signal;
• and
• wherein said relay station is further for receiving and demodulating said second spread spectrum signal to provide said power adjustment information, and in response to said power adjustment information adjusting said first predetermined transmission level to maintain a predetermined level of signal quality of said first information signal at said remote user communication station.

In a cellular mobile telephone system in which system users communicate information signals between one another via a system controller and through at least one cell-site using code division multiple access (CDMA) spread spectrum communication signals between said cell-sites and mobile telephones, wherein each cell-site has a plurality of modules for communicating with mobile telephones in said cellular mobile telephone system, a power adjustment system for adjusting cell-site module transmission signal power in response to a power adjustment request from a mobile telephone, wherein each mobile telephone has an antenna, transmitter and receiver and each cell-site has an antenna, at least one transmitter and at least one receiver, said power adjustment system comprising:

• means for determining transmission signal quality at a mobile telephone in a CDMA communication signal directed to said mobile telephone as transmitted from a cell-site module for generating a power adjustment request in accordance with said determined transmission signal quality, and for communicating said power adjustment request to said module;
• means at said module for communicating said power adjustment request to a system controller;
• means at said system controller responsive to said power adjustment request for generating and communicating a power adjustment command to said module;
• means at said module for receiving said power adjustment command, said module responsive thereto for adjusting transmission signal power in said CDMA communication signal to said mobile telephone by a predetermined increment.

In a cellular mobile telephone system in which system users communicate information signals between one another via a system controller and through at least one cell site using code division multiple access (CDMA) spread spectrum communication signals between said cell-sites and mobile telephones, wherein each cell-site has a plurality of modules for communicating with mobile telephones in said cellular mobile telephone system, a method for adjusting cell-site module transmission signal power in response to a power adjustment request from a mobile telephone, wherein each mobile telephone has an antenna, transmitter and receiver and each cell-site has an antenna, at least one transmitter and at least one receiver, said power adjustment method comprising the steps of:

• determining, at a mobile telephone, transmission signal quality in a CDMA communication signal directed to said mobile telephone;
• generating, at said mobile telephone, a power adjustment request when said determined transmission signal quality is below a predetermined signal quality level;
• communicating said power adjustment request to said module;
• communicating said power adjustment request from said module to a system controller;
• generating a power adjustment command responsive to said power adjustment request at said system controller;
• communicating said power adjustment command to said module;
• receiving said power adjustment command at said cell-site module and
• adjusting transmission signal power in CDMA communication signal to said mobile telephone by a predetermined increment.

In a cellular mobile telephone system in which system users communicate information signals between one another via a system controller and through at least one cell-site using code division multiple access (CDMA) spread spectrum communication signals between said cell-sites and mobile telephones, wherein each cell-site has a plurality of modules for communicating with mobile telephones in said cellular mobile telephone system, a power control system for adjusting cell-site module transmission signal power in response to a power adjustment request from a mobile telephone, wherein each mobile telephone has an antenna, transmitter and receiver and each cell-site has an antenna, at least one transmitter and at least one receiver, said power control system comprising:

• a mobile station receiver for receiving a signal from a cell base station;
• a processor coupled to said receiver for determining a signal quality level for said received signal and providing a power adjustment request if said signal quality level falls below a predetermined value;
• a transmitter coupled to said processor responsive to said power adjustment request for transmitting said power adjustment request;
• a cell base station receiver for receiving said power adjustment request from said mobile station;
• a system controller coupled to said cell base station for processing mobile station information;
• and
• a cell base station transmitter coupled to said cell base station receiver and responsive to said power adjustment request for adjusting the transmission power of said signal.

A method for controlling transmission power in a communication system comprising the steps of:

• spread spectrum modulating an information signal;
• transmitting said spread spectrum modulated information signal at a predetermined power level in a first spread spectrum signal from a first communication station;
• receiving said first spread spectrum signal at a second communication station;
• demodulating said received first spread spectrum signal to recover said information signal;
• determining signal quality of said recovered information signal;
• generating power adjustment information corresponding to said determined signal quality;
• spread spectrum modulating said power adjustment information;
• transmitting said spread spectrum modulated power adjustment information in a second spread spectrum signal from said second communication station;
• receiving said second spread spectrum signal at said first communication station;
• demodulating said second spread spectrum signal to recover said power adjustment information;
• and
• modifying said predetermined power level according to said power adjustment information.

In a cellular mobile telephone system in which system users communicate information signals between one another via a system controller and through at least one cell-site using code division multiple access (CDMA) spread spectrum communication signals between said cell-sites and mobile telephones, wherein each cell-site has a plurality of modules for communicating with mobile telephones in said cellular mobile telephone system, a power adjustment system for adjusting cell-site module transmission signal power in response to a power adjustment request from a mobile telephone, wherein each mobile telephone has an antenna, transmitter and receiver and each cell-site has an antenna, at least one transmitter and at least one receiver, said power adjustment system comprising:

• means for determining transmission signal quality, at a mobile telephone for CDMA communication signals intended for said mobile telephones transmitted from a cell-site module, with respect to a desired signal quality level, for generating a power adjustment request when said determined transmission signal quality is below said desired signal quality level, and for communicating said power adjustment request to said module;
• and
• means for adjusting module transmission signal power in CDMA communication signals transmitted to said mobile telephone by a predetermined increment in response to said power adjustment request.