Abstract: A packet mode (e.g. IP) group communication service layer is provided on top of a standard mainstream cellular radio network. Conceptually, the group communication layer includes a pair of basic logical entities, an application bridge and a call processing server (CPS). The bridge and the CPS run group service applications which communicate with group service application(s) in a mobile station MS over the IP connections provided by the radio network. The CPS is responsible for control plane management of group communications. The bridge is responsible for the real-time distribution of VoIP packets to the user terminals according to their group memberships over valid connections programmed by the CPS.

Abstract: A packet mode (e.g. IP) group communication service layer is provided on top of a standard mainstream cellular radio network. Conceptually, the group communication layer includes a pair of basic logical entities, an application bridge and a call processing server (CPS). The bridge and the CPS run group service applications which communicate with group service application(s) in a mobile station MS over the IP connections provided by the radio network. The CPS is responsible for control plane management of group communications. The bridge is responsible for the real-time distribution of VoIP packets to the user terminals according to their group memberships over valid connections programmed by the CPS.

Abstract: A packet mode (e.g. IP) communication service layer is provided on top of a standard mainstream cellular radio network. Conceptually, the communication layer comprises a pair of basic logical entities, an application bridge and a call processing server (CPS). The bridge and the CPS run packet mode communication service applications, which communicate with packet mode communication service application(s) in a mobile station MS over the IP connections provided by the radio network. The CPS is responsible for control plane management of communications. Embedded user-plane signaling is used for connecting call parties for a packet mode speech two-party (one-to-one) communication. Embedded signaling in the user-plane's bearer makes it unnecessary to reserve another bearer for the control plane's signaling, which saves network resources and allows to achieve a short connection setup time.

Abstract: A packet mode (e.g. IP) group communication service layer is provided on top of a standard mainstream cellular radio network. Conceptually, the group communication layer comprises a pair of basic logical entities, an application bridge and a call processing server (CPS). The bridge and the CPS run group service applications which communicate with group service application(s) in a mobile station MS over the IP connections provided by the radio network. The CPS is responsible for control plane management of group communications. The bridge is responsible for the real-time distribution of VoIP packets to the user terminals according to their group memberships over valid connections programmed by the CPS.

Abstract: A packet mode (e.g. IP) communication service layer is provided on top of a standard mainstream cellular radio network. Conceptually, the communication layer comprises a pair of basic logical entities, an application bridge and a call processing server (CPS). The bridge and the CPS run packet mode communication service applications, which communicate with packet mode communication service application(s) in a mobile station MS over the IP connections provided by the radio network. The CPS is responsible for control plane management of communications. Embedded user-plane signaling is used for connecting call parties for a packet mode speech two-party (one-to-one) communication. Embedded signaling in the user-plane's bearer makes it unnecessary to reserve another bearer for the control plane's signaling, which saves network resources and allows to achieve a short connection setup time.

Abstract: A packet mode (e.g. IP) group communication service layer is provided on top of a standard mainstream cellular radio network. Conceptually, the group communication layer comprises a pair of basic logical entities, an application bridge and a call processing server (CPS). The bridge and the CPS run group service applications which communicate with group service application(s) in a mobile station MS over the IP connections provided by the radio network. The CPS is responsible for control plane management of group communications. The bridge is responsible for the real-time distribution of VoIP packets to the user terminals according to their group memberships over valid connections programmed by the CPS.

Abstract: In a radiotelecommunications system where some of the subscriber stations are able to communication with one another on a direct mode channel, to direct subscriber stations to one and the same direct mode channel, a command that contains the channel identifier of the direct mode channel is sent to the subscriber stations. The subscriber stations move, in response to the channel identifier, to the direct mode channel indicated by the channel identifier, whereby each subscriber station is able to communicate with the other subscriber stations directed to same direct mode channel.

Abstract: A channel allocation method in a cellular radio system. The mobile radios have permanently stored in their memories a first group of radio channels scanned in a normal hunt sequence and a second group of radio channels scanned in a comprehensive hunt sequence. When the control channel of a base station is changed, a channel permanently belonging to the first group is allocated as a new control channel to the base station whenever such a channel is available. If a channel belonging to the second group has to be allocated as a control channel, it is transferred temporarily to the first group and the change of group is announced through control channels to the mobile radios. A channel permanently belonging to the first group is re-established as the control channel of a base station as soon as such a channel is available and the freed channel is returned to the second group.

Abstract: A method of searching for a signalling channel in a radio system including a mobile exchange, base stations connected therewith, subscriber stations that are connected with the base stations and communicate with the radio system via the channels of the base station, i.e. via traffic channels and non-dedicated control channels. The method includes the following steps: a first subscriber station registered in a first base station listens to a signalling channel of the first base station, and the radio system allocates the signalling channel to a second subscriber station for use as a traffic channel since the other channels of the first base station are busy.

Abstract: A call control method for a radio system, wherein a half-duplex type mobile station (MS1, MS2) is commanded so as to clear a call on the radio channel of a base station (BS), by transmitting a disconnect signal to the mobile station (MS1, MS2) over the radio channel, the mobile station leaving the radio channel upon receiving the disconnect signal. In order to ensure that the disconnect signal is received by the mobile station, the field intensity received by the base station (BS) on the radio channel is measured immediately after the transmission of the disconnect signal, and the radio channel is released for the next call only when the measured field intensity falls below a predetermined threshold value.