1
POWERED DOWN SELECTION OF A
PREFERABLE WIRELESS
COMMUNICATIONS SERVICE PROVIDER
IN A MULTI-SERVICE PROVIDER
ENVIRONMENT 5
CROSS REFERENCE TO RELATED
INVENTION
This is a Continuation of application Ser. No. 08/570,902 filed Dec. 12, 1995.
This application is related to commonly assigned and concurrently filed U.S. patent applications entitled "A Method For Selecting A Wireless Communications Service Provider In A Multi-Service Provider Environment", A ^ Method For Selecting a Preferable Wireless Communications Service Provider In a Multi-Service Provider Environment, and Method For Selecting a Wireless Service Provider In a Multi-Service Provider Environment Using a Geographic Database Ser. No. 08/570,905 filed Dec. 12, 20 1995, Ser. No. 08/570,904 filed Dec. 12, 1995, and Ser. No. 08/570,903 filed Dec. 12, 1995.
BACKGROUND OF THE INVENTION
1. Field of the Invention 25 The present invention relates to communications; more
specifically, communications in a multi-service provider environment.
2. Description of the Related Art 30 FIG. 1 illustrates a portion of the radio frequency spectrum. Frequency range 10 centered around 800 MHz has historically been known as the cellular frequency range and frequency range 12 centered about 1900 MHz is a newer defined frequency range associated with personal commu- 35 nication services (PCS). Each range of frequencies, i.e., the cellular and PCS, are broken into two portions. In cellular frequency range 10, there is uplink portion 13 which is used for communications from a mobile communication device to
a base station such as a cellular base station. Portion 16 of 40 cellular frequency range 10 is used for downlink communications, that is, communications from a cellular base station to a mobile communication device. In a similar fashion, Portion 18 of PCS frequency range 12 is used for uplink communications, that is, communications from a 45 mobile communication device to a base station. Portion 20 of PCS frequency range 12 is used for downlink communications, i.e., communications from a base station to a mobile communication device.
Each of the frequency ranges are broken into bands which 50 are typically associated with different service providers. In the case of cellular frequency range 10, frequency bands 30 and 32 are designated band "a" for uplink and downlink communications, respectively. In a particular geographic area, a cellular service provider is assigned frequency band 55 "a" in order to carry out mobile communications. Likewise, in the same geographic area another cellular service provider is assigned frequency bands 34 (uplink) and 36 (downlink) which are designated band "b". The frequency spectrums assigned to the service providers are separated so as to not 60 interfere with each other's communications and thereby enable two separate service providers to provide service in the same geographic area. Recently, the US Government auctioned the PCS frequency spectrum to service providers. As with the cellular frequency range, the PCS frequency 65 range is broken into several bands where a different service provider may use a particular frequency band for which it is
2
licensed within a particular geographical area The PCS bands are referred to as A, B, C, D, E and F. The A band includes uplink band 50 and downlink band 52. The B band includes uplink band 54 and downlink band 56. Band C includes uplink band 58 and downlink band 60. Each uplink and downlink band of the A, B and C bands are approximately 30 MHz wide. The D band includes uplink band 62 and downlink band 64. The E band includes uplink band 66 and downlink band 68. Likewise, band F includes uplink band 70 and downlink band 72. The uplink and downlink bands of bands D, E and F are approximately 10 MHz wide each. It should be noted that with the cellular and PCS frequency bands, it is possible to have as many as eight different wireless communication service providers in a particular area
Each of the different cellular and PCS bands consist of control channels and communication channels in both the uplink and downlink direction. In the case of analog cellular bands, there are 21 control channels for both the "a" and "b" bands. Each of the control channels include an uplink and a downlink portion. The control channels transmit information such as an SOC (System Operator Code), an SID (System Identifier Code), paging information call setup information and other overhead information such as information relating to registering with the mobile communication system. The portion of the cellular band's spectrum not occupied by the control channels is used for communication channels. Communication channels carry voice or data communications, where each channel consists of an uplink and downlink communications link. Presently there are several cellular communication standards. An analog standard known as EIA/TIA 553 was built upon the AMPS (Advanced Mobile Phone Service) standard. This standard supports 21 analog control channels (ACC) and several hundred analog voice or traffic channels (AVC). A newer standard is the EIA/TIA IS54B standard which supports dual mode operation. Dual mode operation refers to having an analog control channel, and either an analog voice/traffic channel or a digital traffic channel (DTC). The AVC or DTC are used for actual communications, and the ACC is used to transfer information relating to, for example, call set-ups, service provider identification, and the other overhead or system information.
A newer standard, the EIA/TIA IS136 standard supports communications covered by both analog and dual mode cellular, and also includes a totally digital communication scheme which was designed for the PCS frequency bands A-F and cellular frequency bands "a" and "b". This standard allows for a digital traffic channel (DTC) and a digital control channel (DCCH). In the case of the DTC, not only is the voice or data communicated, but in addition, a digital channel locator (DL) is transmitted in the DTC. The DL enables a mobile communication device that locks onto the DTC to use the information in the DL to locate a DCCH for purposes of obtaining information such as the SOC, SID, paging information, and other system overhead information carried on the digital control channel.
When a mobile communication device such as a mobile telephone attempts to register with the service provider, it locks onto a control channel and reads information such as the SOC and SID. If the SOC and/or SID correspond to a service provider with which the user has a communication services agreement, the telephone may register with the service provider's mobile communication system via the up-link control channel.
FIG. 2 illustrates a map of the United States illustrating cities such as Seattle, Chicago and Washington, D.C. For example, in Seattle frequency band A has been licensed to
