Abstract: The present invention discloses a carrier selection method for reducing interferences between mobile stations and/or base stations. A measure associated with a probability for a mobile station, having access to at least two carrier duplex entities, to produce interferences with adjacent external spectrum blocks is obtained. A candidate carrier duplex entity is then selected based on the interference measure. If the measure is lower than a first threshold value an inner carrier duplex entity should be selected as candidate carrier duplex entity. A mobile station in idle mode then locks to a downlink carrier of the candidate carrier duplex entity upon locking into a system. Mobile stations in an idle locked mode relocks to the downlink carrier of the carrier duplex entity, whereas mobile stations in an active mode perform a carrier handover to the candidate carrier duplex entity, unless already locked thereto.

Abstract: In the present invention, carrier pairs of one uplink carrier (UL1, UL2) and one downlink carrier (DL1, DL2) are provided with a flexible duplex frequency separation distance in a cellular communication system (1) operating according to a FDD concept. At least a first carrier pair used in the system has a different duplex frequency separation distance than a second carrier pair. The duplex frequency separation distance may vary within one cell (12H, J) and/or between different cells (12H, J) in the same system (1), preferably dependent on the traffic situation and preferably on a per connection or per code basis.

Abstract: A method and apparatus for providing handover between carriers of different duplex frequency separation distances is provided. A mobile terminal is configured to operate in both fixed and variable duplex. The ability operate with unpaired up-link and down-link frequency carrier pairs, when necessary, makes it possible to significantly increase the spectrum utilization (capacity) in a cellular system using asymmetric up-link and down-link for example in WCDMA systems.

Abstract: In an installation for transmitting alarms, preferably in connection with attacks on persons, and for locating the alarm sender, there is at least one portable alarm sender 2 sending an alarm to a central alarm receiver (3) by radio. The senders each contain a memory (24) for a code unique to their position in the installation. The code is automatically set by fixed transmitters (1) having a small range, which transmit it electromagnetically, especially inductively, to the sender (2), the code being unique to the location of a transmitter and stored in the sender memory. When fixed transmitters (1) are arranged so close together that their unique codes are difficult to separate in the sender (2), a dummy transmitter (56) is arranged to prevent alteration of a code already stored in the memory (24) of the alarm sender, as long as the sender (2) is close to the dummy transmitter (56).