Abstract: Voice recording and playback mode using the G.726 half-rate within the personal handy phone system (PHS). When a portable station within the PHS operates as a voice recorder (e.g., functioning as an answering machine), a cost effective system in accordance with the present invention is adapted to compress and store received voice/sound signals in order to increase the usage of limited memory resources provided within the portable station. The present invention also enables previously compressed and stored voice/sound signals to be decompressed and played back in various portable station playback modes. Specifically, the portable station receives a voice/sound signal in a full rate (e.g., 32 kilobits-per-second) 4-bit adaptive differential pulse code modulation (ADPCM) data format in compliance with the International Telecommunication Union (ITU) recommendation G.726.

Abstract: The present invention provides methods of transmitting information within a personal handy-phone system wireless local loop and personal handy-phone system wireless local loops. One embodiment of a personal handy-phone system wireless local loop according to the present invention comprises: a base station; a repeater station configured to transmit a plurality of uplink radio signals to the base station and receive a plurality of downlink radio signals from the base station; and a portable station configured to transmit the downlink radio signals to the repeater station and receive the uplink radio signals from the repeater station.

Abstract: A method for remotely updating software code of personal handy phone system equipment. The present invention enables a remotely located control terminal to update stored software code within a distant portable station or cell station of the personal handy phone system. Specifically, by coupling a control terminal to the existing communication network of a personal handy phone system, the control terminal is able to communicate with portable stations and cell stations. To update the software code of a specific portable station or cell station, the control terminal first establishes communication with that particular device by sending an unique preparatory signal addressed to it. The addressed device receives the unique preparatory signal and checks the validity of it. If the addressed device determines the unique preparatory signal is valid, it transmits a unique verification signal addressed to the control terminal indicating that it is ready to receive the updated version of the software code.

Abstract: A circuit arrangement on a handset for checking paging information transmitted in a personal handyphone system. The circuit arrangement includes a memory portion for storing the identification numbers of the handset and the cell station from which the handset receives calls, and an interrupt generator for comparing transmitted identification numbers of a called handset and a cell station with the stored identification numbers of the handset and the cell station and for generating an interrupt when the stored identification number of the handset matches the transmitted identification number of the called handset and the stored identification number of the cell station matches the transmitted identification number of the cell station.

Abstract: Voice recording and playback mode using the G.726 half-rate within the personal handy phone system (PHS). When a portable station within the PHS operates as a voice recorder (e.g., functioning as an answering machine), a cost effective system in accordance with the present invention is adapted to compress and store received voice/sound signals in order to increase the usage of limited memory resources provided within the portable station. The present invention also enables previously compressed and stored voice/sound signals to be decompressed and played back in various portable station playback modes. Specifically, the portable station receives a voice/sound signal in a full rate (e.g., 32 kilobits-per-second) 4-bit adaptive differential pulse code modulation (ADPCM) data format in compliance with the International Telecommunication Union (ITU) recommendation G.726.

Abstract: A method and system that enables an automatic delay setting within a wireless local loop system. The present invention determines the transmission distance time delay existing between a base station and a personal station by employing the communication interface that is utilized between them. The main reason for determining the transmission time delay caused by large transmission distances (e.g., over 300 meters) existing between base stations and personal stations is to compensate for it. Once the transmission distance time delay is known, the personal station utilizes that value to compensate for it. Specifically, the present invention directs a base station to transmit a control signal to a personal station. The personal station receives the control signal and transmits a signal to the base station. The base station determines if it started to receive the signal from the personal station later than it expected the signal to arrive, assuming close proximity of the two stations.

Abstract: The present invention provides methods of synchronization, personal handy-phone system stations, and phase lock loops. Synchronization of a personal handy-phone system station with a telecommunication network, and another communication station are provided. One method of synchronization comprises: providing a counter configured to generate a plurality of counter values; storing a first counter value; detecting a reference event; latching a second counter value responsive to the detecting of the reference event; comparing the first counter value and the second counter value to detect phase drift; and compensating for phase drift responsive to the comparing.

Abstract: A system for a direct digital down conversion of a 10.8 MHz intermediate frequency signal in the personal handy phone system. The present invention includes a system that enables a direct digital down conversion of a 10.8 MHz intermediate frequency signal into a digital baseband signal within cell stations and portable stations of the personal handy phone system. To perform this direct digital down conversion of a 10.8 MHz intermediate frequency signal, one embodiment of the present invention uses a hard limiter circuit, a sampler circuit and a digital down converter circuit. The hard limiter circuit of the present invention receives a 10.8 MHz intermediate frequency signal, utilized within cell stations and portable station of the personal handy phone system, and provides a threshold for it. The sampler circuit uses a 19.2 MHz oscillating clock signal to sample the intermediate frequency signal that is output from the hard limiter circuit. Due to spectral leakage, the 10.

Abstract: The present invention provides methods of analyzing a radio signal, including a personal handy-phone system radio signal. In accordance with a first aspect of the present invention, a method of analyzing a radio signal in a transceiver selectively coupled with a first antenna and a second antenna comprises: receiving a radio signal comprising a plurality of slots via the first antenna; first configuring the transceiver to receive via the first antenna; during the receiving of a selected slot, first determining a radio signal characteristic; following the first determining and during the receiving of the selected slot, second configuring the transceiver to receive via the second antenna; and following the second configuring and during the receiving of the selected slot, second determining a radio signal characteristic.

Abstract: A method and system that enables a wireless repeater within the personal handy phone system to switch the communication mode of each slot within its communication interface. Specifically, the repeater is able to function as a cell station while communicating with a portable station and function as a portable station while communicating with a cell station. For instance, when the repeater communicates with a cell station, it switches the communication mode of a desired slot within its communication interface into portable station communication mode. Conversely, when the repeater communicates with a portable station, it switches a desired slot within its communication interface into cell station communication mode. Since a repeater implemented with the present invention is able to switch the communication mode of each slot within its communication interface, the amount of internal circuitry required within the repeater is significantly reduced.

Abstract: A circuit arrangement on a handset for monitoring changes in the system parameters of a personal handyphone system by hardware checking the broadcasting reception indication (BRI) pattern. The circuit arrangement includes a memory portion for storing the previous BRI pattern received at the circuit arrangement, and an interrupt generator for comparing the stored previous BRI pattern with a current BRI pattern and for generating an interrupt to activate the handset processor when the previous BRI pattern differs from the current BRI pattern.

Abstract: The present invention provides methods of synchronization, personal handy-phone system stations, and phase lock loops. Synchronization of a personal handy-phone system station with a telecommunication network, and another communication station are provided. One method of synchronization comprises: providing a counter configured to generate a plurality of counter values; storing a first counter value; detecting a reference event; latching a second counter value responsive to the detecting of the reference event; comparing the first counter value and the second counter value to detect phase drift; and compensating for phase drift responsive to the comparing.

Abstract: A system that enables a portable station of the personal handy phone system to support a conference call. The present invention provides this capability by empowering a portable station to communicate with up to four cell stations simultaneously enabling the user of the portable station to communicate with the users of four other telecommunication devices. Specifically, the present invention modifies the internal circuitry of a portable station to increase the number of receiving channel circuits to four and the transmitting channel circuits to four while adding a digital signal processor to mix the different received and outgoing voice signals. The increased number of receiving and transmitting channel circuits enables a portable station to utilize all the communication slots located within the frames of the radio communication interface of the personal handy phone system. Communication is time-multiplexed across these slots.

Abstract: A circuit arrangement for hardware checking the validity of data transmitted in a SA-field within the traffic channel of the personal handyphone system. The circuit arrangement includes a receiver for receiving control information corresponding to a SA-field, and an interrupt generator for generating an interrupt to activate the handset processor when the control information indicates the SA-field is the beginning of a series of SA-fields containing valid data.

Abstract: A digital to analog converter (DAC) offset autocalibration system in a digital synthesizer integrated circuit. The present invention includes a DAC coupled to a filter. The input of the DAC accepts digital values for conversion to an analog signal. The output of the DAC is coupled to the input of the filter. The filter smoothes the analog signal received from the DAC. A switch is coupled to the filter output to receive the analog signal. A comparator is coupled to the switch. The input of the comparator receives the analog signal from the filter output via the switch. An autocalibration control circuit is coupled to the output of the comparator, to the switch, and to the DAC. The autocalibration control circuit is adapted to input a value to the DAC in order to determine an offset correction from the output of the comparator and adjust the analog signal using the offset correction.

Abstract: A key handling circuit for a switching matrix having row and column conductors includes bidirectional drives for the row conductors and the column conductors. The row drive and the column drive are in a low conductive condition except when a relevant key switch is activated. The row drive provides a current input for the column drive in one phase of operation and the column drive provides a current input for a row drive in a second phase of operation.

Abstract: A hardware timing system for a cellular telephone comprises a master counter and a slave counter. The slave counter controls timing window generators in synchronism with the time frame of the local base station. The phases of timing frames of other base stations are monitored using the master counter.