An apparatus is disclosed for a cellular mobile communication system utilizing a spread spectrum. A plurality of fixed base stations is connected with a central processor so that calls originating in any cell can terminate in any other cell. The available frequency spectrum is divided such that one-half is used for mobile-to-base station transmission and the other one-half is used for base station-to-mobile unit transmission. A power control/mobile locator system and method is utilized in all mobile units to compensate for changes in signal level and to maintain the average received signal level at the base station constant regardless of the location of the mobile unit within the cell. In addition, each mobile unit has a unique set of time-frequency coded waveforms that are used for both transmission and reception. The waveforms have large time-bandwidth products so that interfering signals are well suppressed, and which provide a large set of signals so that each user can be assigned a unique set of waveforms. Message modulation is accomplished by digitizing the speech and encoding the resulting binary sequences into the set of waveforms available to the user, while detection is accomplished by a demodulation system and method in which the phases of each received waveform are compared with those of the preceding waveform.

In a cellular telephone system a system for directing communications between a mobile user and cell-sites as a mobile user changes cell-site service areas. The mobile user includes an apparatus for, while in communication with another system user via one cell-site, determining a transition of the mobile user from the cell-site service area to the service area of another cell-site. The system includes circuitry responsive to the indication for coupling communications between the mobile user and the other system user via the new cell-site while the mobile user also remains in communication with the system user via the first cell-site. The system further includes apparatus responsive to the coupling of the communications between the mobile user and the other system user via the new cell-site for terminating the communications between the mobile user and another system user via cell-site with communications continuing between the mobile user and the system user via the new cell-site.

A control system for mobile radio communication, in which the whole service area is composed of a plurality of small radio service zones in each of which communication is sufficiently possible with the transmitting power of any of mobile stations belonging to the service zone, a base station of each of the small radio service zones and a control station for controlling the whole service area are interconnected through a binary code transmission line, and in order to prevent simultaneous transmission of the control signal from a plurality of mobile stations when the mobile stations in the whole service area achieve transmission and reception of the control signal between each of them and the control station over a common control channel, the control station transmits to the mobile stations information representative of the busy or idle status of the common control channel from the mobile stations by the interruption and transmission of an idle line indication signal. By reversing the signal state of the binary code transmission line to its normal state, information of the detection of transmission from the mobile stations by the base stations is transmitted to the control station, and in the control station, the idle channel indication signal is interrupted by the earliest one of the reversed signals arriving from the plurality of base stations. The start of the control signal is indicated by restoring the signal state of the binary code transmission line to its normal state. The control station resumes transmission of the idle channel indication signal upon completion of the reception of the control signal.

An array of antennas for a cellular RF communications system for providing communications to randomly placed transceivers in a given area. The antenna array includes a plurality of antenna sites located in the centers of cells. Each antenna site has a plurality of sectored antennas for providing a plurality of communication channels. A predetermined number of sites are used to constitute a subarray of cells to provide a set of communication channels and channel allocations are repeated from subarray to subarray. Channels are also so allocated as to minimize channel interference and optimize channel utilization. An omnidirectional antenna may be provided for each antenna site for signalling purposes.

In a multi-channel mobile radio telephone system with multiple base stations covering different geographical areas, mobiles may move freely from area to area and automatically originate and receive calls to and from a landswitched telephone network by direct dialing to and from anywhere in the system by means of a Roving Mobile Call System (RMCS). Mobile subscribers operating out of range of their home base stations (where they are registered for billing purposes) may originate any class of call via any base station in the system and be billed by the home base station by means of intercommunicating base stations in a Roving Mobile Ticketing System (RMTS). Provision is made for tariff sharing as necessary by participating stations. All call signalling and central signalling is performed out-of-band. Call signalling from any base station to mobiles is common to all radio channels transmitted by that station. Mobiles may be in the standby condition on any radio channel regardless of whether it is in use for communications purposes or not. Mobiles are directed to various channels for communications by the terminal equipment.