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.