Abstract: A compact low-power radio frequency (RF) transceiver with a built-in antenna provides wireless communication between a computer and another device. A direct conversion receiver together with a voltage controlled oscillator, phase lock loop circuits, digitally controlled divider circuits and a patch antenna are packaged into a compact enclosure, having dimensions within the PCMCIA format. In some embodiments, the transceiver enters a sleep mode whenever it is idle in order to further conserve power. In other embodiments, a signature detector enables the transceiver to distinguish between noise and valid messages by recognizing a signature word embedded in the data packet.

Abstract: A portable computer and telecommunications equipment unit has the functions of a mobile telephone and a computer in a single apparatus. Both functions can be used in an optimum manner either separately or simultaneously. The modular computer and telecommunications equipment is approximately the size of an elongated wallet and has a top module with a telecommunication system. The outer face of the top module carries a telephone keyboard and a telephone display, and its inner side carries a flat display that acts as a computer display. The equipment further has a second underlying module that contains a computer. The top and underlying modules are pivotably interconnected by a hinge. Additional modules that constitute functional extensions or additional energy supply units may be mounted on or in the second module.

Abstract: According to exemplary embodiments of the present invention, multiple hyperband capable mobile stations and base stations are described. These mobile and base stations support multiple hyperband operations including, for example, mobile assisted channel allocation (MACA), mobile assisted handover (MAHO), cell reselection, traffic channel assignment, control channel location and registration. By bridging multiple hyperbands, service quality can be enhanced.

Abstract: The specification relates to a radio frequency (RF) multiport, multiband semiconductor and transmission circuit. Each port in the multiport circuit is linked to a second port utilizing a semiconductor switching leg. A semiconductor switching leg is biased to either transport thereover an RF signal or to prevent its transport. In an embodiment of the present invention utilizing diodes as an active device within each semiconductor switching leg, a DC biasing signal is applied through an inlet and outlet inductor, thus allowing DC current to pass through the diode for biasing, but preventing RF signal loss to ground. Capacitors are used for RF signal coupling and DC blocking. One embodiment of the present invention is utilized with a dual band cellular/PCS device, with either band selectable for transmission and reception over either an internal antenna or, in the alternative, an external antenna port.

Abstract: A mobile communication system involves a mobile space defined in, for example, a train, and mobile terminals available in the market. When the mobile terminals are used in the mobile space, the system provides them with value-added services exclusive to the mobile space. The system also includes existing base stations each controlling a fixed radio zone that covers a predetermined area, and a mobile base station for controlling a mobile radio zone allocated to the mobile space where the mobile terminals are used. The mobile base station serves as a mobile base station to communicate with the existing base stations, and as a fixed base station to communicate with the mobile terminals when the mobile terminals are in the mobile radio zone. Also provided is a method of controlling such a system.

Abstract: When a power failure occurs, a control unit 107 of a main apparatus 101 acquires the outside line 102a through an outside line I/F unit 102 and transmits a signal for requesting terminating transfer and a signal for designating a transfer destination to a public network 108 while receiving power from a backup power supply 106M. After this terminating transfer is requested, and an incoming call to the telephone number of an outside line 102a is received, the public network 108 calls the transfer destination designated for terminating transfer. If the telephone number for calling a radio telephone set 109 from a public base station 113 is designated as this transfer destination, the public base station 113 calls the radio telephone set 109 in a terminating transfer operation.

Abstract: A communications operating system is provided herein. The communications operating system having a common communication system comprising a radio frequency transceiving means for transmitting and receiving radio frequency signals and a system list means for storing a list of communication systems available. The system also includes a feature list means for storing a list of feature programs, where the feature programs comprise at least one of an enabling program to enable resident functions, a high-level design specification, and an executable feature specification.

Abstract: A mobile communication terminal is provided with a GPS receiver and detects a movement velocity of the mobile communication terminal based on GPS data. The period of time in which the channel condition of a radio channel is monitored is changed according to the movement velocity. The lower the movement velocity of the mobile communication terminal, the longer the period of time in which the radio channel is intermittently monitored. The radio channel is periodically monitored in a period of time changed according to the movement velocity of the mobile communication terminal. Channel switching is performed from a radio channel being used to a neighboring radio channel when the channel condition of the neighboring radio channel is better than that of the radio channel being used.

Abstract: A local broadcast mode operation is implemented in a point-to-point satellite communications system (10) by utilizing a terrestrial reference terminal or phone (20) that is located within a desired zone of broadcast operation (24). A broadcast service provider (16) places a call to this reference phone through a terrestrial gateway (12) and at least one satellite (18, 19), and then transmits desired broadcast data to the reference phone. The reference phone receives the broadcast data and functions in a conventional manner to provide power control and related satellite handoff feedback information to the gateway. Authorized user terminals (22) within the zone of broadcast operation are enabled to receive the same signal transmitted to the reference phone by placing a call through the gateway to the broadcast service provider.

Abstract: An apparatus for reducing undesirable low-frequency distortion in a direct conversion communication receiver includes a signal generator to produce a first periodic signal and a second periodic signal. A merge circuit combines an input signal and the first periodic signal to produce a modulated signal with a polarity switched component. A frequency translation circuit converts the modulated signal into a baseband signal with a spectrum substantially equal to the modulated signal, but centered around a carrier frequency of approximately zero and including a low-frequency error component. An output modulator circuit combines the baseband signal with the second periodic signal to produce a modified baseband signal wherein the low-frequency error component is shifted to a high frequency spectrum position and the polarity switched component is eliminated.

Abstract: The housing (12) for a portable device (10) has a cavity (40) which engages a boss (28) on a U-shaped clip (22) to prevent a relative rotation between the housing (12) and the U-shaped clip (22) whenever a force is exerted on the free end of the U-shaped clip (22) when fitted over a belt. The boss (28) is disengaged from the cavity (40) whenever a force is applied which deforms the U-shaped clip (22), thereby allowing the housing (12) to be rotated to view an annunciator presenting a message. The U-shaped clip (22) rotates about a pivot formed by a first boss (26), and second boss (24) having a D-shape, which engage a first bearing (42) and second bearing (44), respectively. The D-shape of the second boss (24) and configuration of the second bearing (44) enable the U-shaped clip (22) to be assembled to/disassembled from the housing (12).

Abstract: The present invention involves an adaptive digital radio communications architecture which can be reconfigured by reprogramming at least one programmable device, and thus more efficiently use the available bandwidth of a time-varying RF channel and/or to provide a flexible and adaptive digital communications system. In certain embodiments, the programmable device uses a Programmable Logic Device (PLD) to perform the digital communications processing functions of the transmitter or the receiver of a radio communications system. In this context, PLD is a general term representing a family of programmable logic devices; examples of this family are a Programmable Array Logic (PAL), a Complex PLD (CPLD), and a Field Programmable Gate Array (FPGA). The architecture is reconfigurable in the sense that any or all of the digital communications processing algorithms can be modified by reprogramming the PLD.

Abstract: A system and method of controlling transmission power during the establishment of a channel in a CDMA communication system utilize the transmission of a short code from a subscriber unit to a base station during initial power ramp-up. The short code is a sequence for detection by the base station which has a much shorter period than a conventional spreading code. The ramp-up starts from a power level that is guaranteed to be lower than the required power level for detection by the base station. The subscriber unit quickly increases transmission power while repeatedly transmitting the short code until the signal is detected by the base station. Once the base station detects the short code, it sends an indication to the subscriber unit to cease increasing transmission power. The use of short codes limits power overshoot and interference to other subscriber stations and permits the base station to quickly synchronize to the spreading code used by the subscriber unit.

Abstract: A method and apparatus for fraud control using enhanced techniques with the call interdiction feature of a switch. A system in accordance with the principles of the present invention includes a fraud control system that monitors calls, identifies both legitimate and fraudulent cellular phones, discriminates legitimate cellular phones from fraudulent cellular phones, and then transmits an interdiction message to the switch, wherein the interdiction message instructs the switch to terminate calls placed from fraudulent cellular phones, while allowing calls placed by legitimate cellular phones to continue undisturbed.

Abstract: A subscriber (410) to a radio communication system manages information needed to monitor for potential server sites during an ongoing communication session. Upon switching server sites during an ongoing communication (520, 530, 540, 550), the subscriber uses a modified neighbor site list for subsequent monitoring for potential server sites (570). The modified list is generated from the original list without benefit of new information downloaded from an external source, by replacing information representing the new server site with information representing the old server site (560).

Abstract: A transmitting and receiving antenna VSWRs (voltage standing wave ratio) measuring circuit of a base station in a mobile communication system comprises: transmitting and receiving antennas for transmitting and receiving a radio frequency signal of a predetermined frequency band in a mobile communication system; transmitting antenna VSWR measuring means for variable-attenuating and detecting a transmitting signal received from the transmitting antenna and sending a transmitting signal strength to a measuring controller whereby to measure transmitting power and reflected power; and receiving antenna VSWR measuring means for variable-attenuating and detecting a receiving signal received from the transmitting antenna and sending a receiving signal strength to a measuring controller whereby to measure receiving power and reflected power.

Abstract: A multiband mobile unit communication apparatus is disclosed which comprises: an antenna for receiving L FRQ bands of M radio wave SIGs modulated by N modulating methods, M>L, M>N, N≧L; a frequency synthesizer for generating a LO SIG; an IF SIG generation CKT for generating M IF SIGs using the LO SIG, the FRQ synthesizer generating the LO SIG such that the M IF SIGs have the same intermediate FRQ; a SW CKT for selectively outputting N IF SIGs modulated by the N modulating methods respectively out of the M IF SIGs; N filters for filtering outputs of N IF SIGs from the SW CKT and outputting N filtered IF SIGs respectively; a SW responsive to a SW CONT signal for selectively outputting one of the N filtered IF SIGs; and a quadrature demodulator for quadrature-demodulating one of N filtered IF SIGs and outputting baseband SIG. Different frequency bands of received signals are converted into IF SIGs having the same intermediate frequency.

Abstract: A method and apparatus for wide range automatic frequency control. A control signal indicating a frequency within one of a plurality of frequency bands is received by an oscillator. In response, the oscillator generates a tuning signal having the indicated frequency. Based on the tuning signal, receive logic receives an input signal to obtain a sequence of values. Compare logic compares the sequence of values to a predetermined pattern. If the sequence of values does not match the predetermined pattern, frequency control logic outputs a different control signal to the oscillator to adjust the frequency of the tuning signal to another one of the plurality of frequency bands. Another input signal is received to obtain a new set of values and the new set of values is compared the predetermined pattern.

Abstract: A base station communicates with a plurality of mobile stations over a cellular network. In one embodiment, the base station includes a transceiver configured to receive inbound information from the mobile station and transmit outbound information to the mobile station. The transceiver equalizes and decodes the inbound information and encodes the outbound information. The transceiver is coupled to a data bus for communicating the inbound and outbound information with the other elements in the base station. The transceiver is also coupled to a control bus. An trunk module is coupled to the data bus and to a mobile services center. The trunk module communicates inbound and outbound information with the mobile services center. The trunk module is also coupled to the control bus. Finally, a central processor is coupled to the control bus to control the transceiver and the trunk module. A preferred protocol is Global Systems for Mobile Communication (GSM).

Abstract: In accordance with the present invention, a communications system transmits a predetermined signal, from a first, sending, end of a communications system to a second, receiving, end of a communications system. The predetermined signal is distorted by the communication system and is received as a distorted signal that is compared to a known version of the originally transmitted signal. A comparison signal related to the difference between the originally transmitted signal (as represented by the known version of the originally transmitted signal) and the distorted predetermined signal as received at the receiving end is employed to adjust the transfer characteristic of a programmable converter to compensate for the distortion introduced by the communication system.