Telefonaktiebolaget Lm Ericsson (publ)

Sony Ericsson Mobile Communications Ab

Bo Lindell

Martin Isberg

Jan Ingemar Swerup

Tomas Pensjö

Björn Lindqvist

Leif Magnus Nilsson

Robert Kristiansson

A control unit supplies a new control value to a frequency source. The value is determined by the frequency source frequency and the reference frequency. The control unit further calculates a rate of change value based at least on the new and a previous control value if there is communication with the reference frequency generator and stores these values in corresponding stores. Another control unit calculates a new control value based on the rate of change value from the rate of change store and the last used control value from the control value store and supplies the new control value to the frequency source if there is no communication with the reference generator.

Oscillator frequency control

The present invention is directed towards a method, a link check device, and a portable communication device for communication link check. The link check device () comprises a receiver unit () for receiving and monitoring information including a power control signal from a base station on a first link (). A first and second signal generating unit () connected to said receiver unit () provide a first and second noise signal (R, R), which are transmitted to a combining unit () to provide a third signal representing signal (R) strength for communication links.

Radio link check

A portable communication device includes a radio circuit for feeding antenna elements, at least one component which is mildly sensitive to external radio transmission, and an antenna arrangement for sending and receiving radio traffic. The antenna arrangement includes a first antenna element located within and extending through a major portion of the device, and a second smaller antenna element connected to the first antenna element. The radio circuit is connected between the two antenna elements and the component is provided on a section of the antenna arrangement making small contributions to the antenna currents in the antenna arrangement.

Placing of components on an antenna arrangement

A portable communication device includes a first part including a first antenna element located within and extending through a portion of the first part and radio circuit feeding antenna elements, a second part hingedly joined to an end of the first part for providing at least one open and one closed position of the phone, and a hinge element connected to the first and second parts. The hinge element stretches along the end of the first part for providing rotation of one part in relation to the other part around a first axis having a first and second end. The hinge element includes a second antenna element. The radio circuit is connected between the first and second antenna elements.

Antenna for portable communication device equipped with a hinge

In a method and apparatus for assigning the values or functions to be represented by the keys of a keypad in a mobile communication device, the keys are capable of representing different values or functions based on the occurrence of a predetermined event. A detector is used to detect the occurrence of the event. Depending on whether the event is detected, the keys are assigned to represent a different set of values or functions.

Method and apparatus for keypad representation in a mobile communication device

A tuning arrangement in a radio receiver includes a front-end circuit having a tunable band-pass filter that is capable of tunably selecting channels within at least one frequency band of an RF signal. A noise source coupled to an input of the tunable band-pass filter introduces a wide-band noise signal into the front-end circuit. A signal detector coupled to an output of the front-end circuit measures at least one signal power associated with a filtered noise signal derived from the wide-band noise signal. A tuning controller, coupled to the tunable band-pass filter by a tuning control signal, adjusts the tuning control signal in response to the at least one measured signal power for tuning the tunable band-pass filter to a desired filter response.

Methods and apparatus for tuning pre-selection filters in radio receivers

The invention relates to a mobile terminal antenna system for a first radio application (RA) and a second radio application (RA) the system comprising first radio electronic circuits (REC) for the first radio application (RA), and second radio electronic circuits (REC) for the second radio application (RA). The system also comprises an end-fed antenna () for the first radio application (RA), the end-fed antenna () having an extended shape and being connected to the first radio electronic circuits (REC). The system comprises a dipole antenna () for the second radio application (RA), the dipole antenna () being located near one end of the end-fed antenna () and connected to the second radio electronic circuits (REC). The first radio electronic circuits (REC) are connected to the dipole antenna (), whereby the end-fed antenna () is adapted to be fed, during transmission, against the dipole antenna () by the first radio electronic circuits (REC), whereby the dipole antenna () is adapted to serve as a counterpoise for the end-fed antenna ().

Device for mobile terminal

The present invention relates generally to the field of RF transmitters, and more particularly to a method and apparatus for increasing the efficiency of transmitters which are capable of transmitting at different power levels in each of at least two frequency bands. An inventive method is presented as well as an inventive transmitter comprising at least one power amplifier in which the load in the transmission line is varied as the output power is varied, in order to keep the efficiency of the power amplifier at a high level.

Method and apparatus for increasing the efficiency of a transmitter

A mobile terminal (), comprising a casing (), which accommodates radio electronic circuits (REC) and a screening device (SD) for the radio electronic circuits, comprises an antenna system comprising an end-fed antenna (EA), having an extended shape, presenting a first end and a second end and being connected to the radio electronic circuits (REC). A counterpoise element () is located near the first end of the end-fed antenna (EA), the end-fed antenna being adapted to be fed against the counterpoise element () by the radio electronic circuits (REC). A tuning network (TN) is located near the second end of the end-fed antenna (EA). The tuning network (TN) is adapted to adjust the electrical length of the antenna so as to assume a value corresponding to a multiple of a half wave-length of the frequencies used.

Arrangement for a mobile terminal

The invention relates to an antenna system for a mobile terminal ( ), comprising a casing ( ), which accommodates radio electronic circuits (REC) and a screening device (SD) for the radio electronic circuits. The antenna system comprises an end-fed antenna ( ), having an extended shape and being connected to the radio electronic circuits (REC). The antenna system comprises a counterpoise element ( ), located near one end of the end-fed antenna ( ), and the end-fed antenna is adapted to be fed, during transmission, against the counterpoise element ( ) by the radio electronic circuits (REC).

The invention provides a solution to the problem of providing an inexpensive and simple compass unit which, nevertheless, compensates automatically for different deviations in the Earth's magnetic field at different places in the world. Briefly, the solution involves an novel electronic compass unit, a method in the operation of the compass unit, and a cellular radio communication system. An electronic compass unit constructed in accordance with the invention and located within an area covered by the radio communication system receives information concerning the local magnetic deviation from the correct direction to the geographic North Pole from a data storage unit which is central to the system, through the medium of a connected radio unit. Information concerning the local magnetic deviation is sent from the central data storage unit to respective radio units from a radio base station situated close to said radio unit, via a downlink.

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Lidingö, Sweden

Bo Lindell