Abstract: A telecommunication system includes a number of radio base stations connected to a telephone network, the base stations forming a link to the network for a number of cordless telephones. Each base station determines in which of a number of predetermined signal strength bands the signal strength of a signal produced by a cordless telephone and received by the base station lies. If the received signal strength lies in a lower band, the base station stores an indication of the signal, and scans through the communication channels available between the base station and the cordless telephones to determine whether a new incoming signal lies in the highest signal band, or whether by increasing the rank of the band of a stored signal, the highest signal band is reached.

Abstract: Two mobile communications handset terminals for a cellular telephone system each incorporate a microprocessor for controlling the operating components of the terminal. Each microprocessor operates under control of software stored in a FLASH Eprom. When the two units are interconnected by a special cable loom, a 12 volt supply of one of the units is applied to the FLASH Eprom of that unit, switching it into a reprogramming mode. This 12 volt supply is also applied via an output terminal to the FLASH Eprom of the other unit which is thus likewise switched into a reprogramming mode. Via the cable loom, each handset compares the grade of the software stored in its FLASH Eprom with the grade of software stored in the other's FLASH Eprom. The handset storing the higher grade software then assumes a MASTER mode and the other one assumes a SLAVE mode. The lower grade software in the SLAVE handset is erased from its FLASH Eprom and replaced with the higher grade software from the MASTER hand set.

Abstract: A communication procedure suitable for a cordless telephone system involves time division duplex radio communication between a handset 11 and a base station 3 using alternating bursts of transmission over a single radio channel. Once a radio link has been set up, initial transmissions carry a synchronisation logical channel S and a signalling logical channel D multiplexed together, but the link may switch to bursts carrying a communications logical channel B for the speech data and the signalling logical channel D. Burst synchronisation is achieved by the asynchronous detection of words in a synchronisation channel S. These words have bit patterns reducing the probability of incorrect asynchronous detection of them. If one part ceases to receive handset signals from the other, it transmits a special signal, informing the other part. This enables both parts to detect the failure of a link at substantially the same time, so that their actions to re-establish the link are synchronised.

Abstract: A mobile radio telephone includes a hand-portable unit 1 and a booster unit 3. A coaxial cable 25 is arranged to produce a link between the intermediate frequency signals produced by the booster unit and RF signals produced by the hand-portable unit 1.

Abstract: A receiver for a mobile telephone system operating in a Time Division Multiple Access (TDMA) system, includes a gain control circuit coupled to receive an input signal, the circuit being switchable under the control of digital control signals between three gain or attenuation levels. An equalizer is coupled to receive the output signal from the gain control circuit. A signal strength unit determines the value of the received signals and provides the digital control signals so as to set the gain or attenuation level constant for a time slot of the TDMA system. The signal strength unit records the determined signal value so as to set the level of said gain control circuit prior to a predetermined time slot based upon measurements made during a preceding time period.

Abstract: A receiver system for a mobile telephone system comprises two or more antenna spaced a distance apart from each other greater than the wavelength of incident radiation, and a receiver. Each antenna is coupled to a respective receiver channel of the receiver, each receiver channel comprising an RF means for processing the received signals, and equaliser means for equalising and/or decoding the signals from the RF means. The equaliser means includes metric generating means for generating metric information which provides probability measures for a sequence of time intervals and for a multiplicity of possible states of the receiver within each time interval that the received signal has put the receiver into the respective states, and selector means for comparing the values of corresponding metrics from respective receiver channels for selecting received data from the receiver channel having the higher probability of accuracy.

Abstract: A communication procedure suitable for a cordless telephone system involves time division duplex radio communication between a handset 11 and a base station using alternating bursts of transmission over a single radio channel. Once a radio link has been set up, initial transmissions carry a synchronization logical channel S and a signalling logical channel D multiplexed together, but the link may switch to bursts carrying a communications logical channel B for the speech data and the signalling logical channel D. Burst synchronization is achieved by the asynchronous detection of words in a synchronization channel S. These words have bit patterns reducing the probability of incorrect asynchronous detection of them. If one part ceases to receive handset signals from the other, it transmits a special signal, informing the other part. This enables both parts to detect the failure of a link at substantially the same time, so that their actions to re-establish the link are synchronized.

Abstract: A communication procedure suitable for a cordless telephone system involves time division duplex radio communication between a handset 11 and a base station 3 using alternating bursts of transmission over a single radio channel. Once a radio link has been set up, initial transmissions carry a synchronization logical channel S and a signalling logical channel D multiple together, bu the link may switch to bursts carrying a communications logical channel B for the speech data and the signalling logical channel D. Bursts synchronization is achieved by the asynchronous detection of words in a synchronization channel S. These words have bit patterns reducing the probability of incorrect asynchronous detection thereof. If one part ceases to receive handset signals from the other, it transmits a special signal to inform the other part. This enables both parts to detect the failure of a link at substantially the same time, so that their actions to reestablish the link are synchronized.

Abstract: A receiver for a mobile telephone system, the receiver having a gain control coupled to receive an input burst signal and being switchable in response to the value of a gain control signal between a plurality of gain values. A detector for detecting the amplitude of said input burst signal, an averager for storing the value of the detected amplitude and a timer operative in response to the detection of said input signal for timing a sequence of measurements of the amplitude of the input burst signal, said averager being operative to compute an average value of the amplitude and to provide a corresponding gain control signal for a subsequent time period.

Abstract: An amplifier arrangement suitable for use in a receiver for use in a telecommunications system is described. The arrangement includes an amplifier and an FET switch arrangement arranged to alter the time constant of the amplifier in dependence upon the incident signal frequency. A balance switch arrangement is arranged such that switching transients of the switch arrangement are cancelled out in the amplifier arrangement.

Abstract: The apparatus is for digitizing demodulated frequency shift key modulated data signals, and comprises a differentiating circuit arranged to receive the demodulated data signal, and produce differentiated pulses at an output thereof. First and second comparators are arranged to receive the differentiated pulses, and compare the pulses with respective reference voltages to generate output pulses when pulses above and below the respective reference voltages are detected. The outputs of the comparators are connected to the set and reset inputs respectively of a flip-flop, causing a digitized form of the input demodulated signal to be generated at an output of the flip-flop.