Abstract: An access-point node to a first network cell of a radio access network, to an access-center node and to a radio access network enable local service providers in rural areas to provide mobile telecommunication at low cost for end users. The access-point node of the invention is configured to establish, maintain, and release a local user-data radio channel, which consists of a first local channel section having as endpoints a first terminal device located in the network cell and the access-point node, and of a second local channel section having as endpoints the access-point node and a second terminal device located in the network cell. The access-point node is configured to exchange packetized user data and control data with an assigned superordinate access-center node for establishing, maintaining and releasing communication between the first terminal device and a third terminal device located outside the network cell. Link cost between the radio access network and the core network may be strongly reduced.

Abstract: An access-point node to a first network cell of a radio access network, to an access-center node and to a radio access network enable local service providers in rural areas to provide mobile telecommunication at low cost for end users. The access-point node of the invention is configured to establish, maintain, and release a local user-data radio channel, which consists of a first local channel section having as endpoints a first terminal device located in the network cell and the access-point node, and of a second local channel section having as endpoints the access-point node and a second terminal device located in the network cell. The access-point node is configured to exchange packetized user data and control data with an assigned superordinate access-center node for establishing, maintaining and releasing communication between the first terminal device and a third terminal device located outside the network cell. Link cost between the radio access network and the core network may be strongly reduced.

Abstract: The present invention relates to a communication system comprising devices (2a-2d) having means for short range communication using a certain frequency band. The frequency band is divided into communication channels. In the communication system some of said communication channels are predefined for establishment of the connection and other communication channels are predefined for data transfer between at least two devices. The present invention also relates to a communication device for communication in a communication system, the device having means for short range communication using a certain frequency band, which is divided into communication channels. The present invention further relates to a method for performing communication in a communication system comprising devices, which have means for short range communication using a certain frequency band, which is divided into communication channels.

Abstract: The present invention relates to a communication system comprising devices (2a-2d) having means for short range communication using a certain frequency band. The frequency band is divided into communication channels. In the communication system some of said communication channels are predefined for establishment of the connection and other communication channels are predefined for data transfer between at least two devices. The present invention also relates to a communication device for communication in a communication system, the device having means for short range communication using a certain frequency band, which is divided into communication channels. The present invention further relates to a method for performing communication in a communication system comprising devices, which have means for short range communication using a certain frequency band, which is divided into communication channels.

Abstract: In a method for compensating D.C. offset in a direct conversion receiver by a signal (IF.sub.-- I, IF.sub.-- Q) received and demodulated in one of the channels of the reception frequency band of a radio communication system, a correction signal (Q.sub.control) is produced from the signals in the channels of the reception frequency band. The correction signal (Q.sub.control) is combined with the demodulated signal. The apparatus for implementing the method comprises means (12, 17, 18, 19) for producing the correction signal, and means (15, 16) for combining the correction signal with the received and demodulated signal.

Abstract: The invention is related to a balanced cuber based predistortion circuit for predistorting an input signal (v.sub.in), comprising a squarer (11) to produce a second order signal and signal dividing means (10', 14') for dividing the input signal and second order signal into differential signals. To produce a third order signal, the input signal and second order signal are mixed in multipliers (15, 16) and the output signals of the multipliers are combined in order to eliminate undesired components. According to the invention, the squarer also includes differential signal handling and combining means (12, 13), advantageously a push-push frequency doubler to produce a second order signal using differential signals. The phase (17) and amplification (18) of the third order signal are adjusted in order to produce a distortion compensation signal, and the input signal (v.sub.in) and distortion compensation signal are combined (19) to produce a predistorted output signal (v.sub.1).