Motorola Corporation

Other

Alexander Rozenstrauch

Rajendra A Panchal

Paul M Erickson

Jay P Jayapalan

Peter M Drozt

Bin Lo

To address the need to provide power control for listening participants of CDMA dispatch services, the concept of 'shared channel signaling windows' for shared traffic channels (e.g.,) is described. In one embodiment, the beginning of a signaling window is announced on the traffic channel and the remote units (e.g., MS) with the highest frame error rates compute the shortest transmit delays. For the duration of the window, remote units transmit their power control signaling according to their transmit delays. Thus, listening participants are given an opportunity, according to need, to perform power control signaling on the group traffic channel.

Method and apparatus for providing power control for CDMA dispatch services

In general, the present invention discloses a method and an apparatus that provide a dispatch patch service in a CDMA communication system (). A communication unit () involved in a dispatch call requests a base site () to patch a patch target (), either a dispatch group or an individual, into the present call. By providing the CDMA long-code mask being used for the present call to the patch target and the dispatch identifier of the patch target to at least the communication unit, a new CDMA long-code mask can be generated and used for the dispatch call going forward.

Method and apparatus for providing a dispatch patch service in a CDMA communication system

To address the need to provide listening participants of CDMA dispatch services soft handoff signaling capability, the concept of 'shared channel signaling windows' for shared traffic channels (e.g.,) is described. In one embodiment, the base site () announces the beginning of a signaling window for the traffic channel, allowing remote units (e.g., MS) that need to send handoff signaling an opportunity. In response to such signaling, the base site directs soft handoff information to the signaling remote units via the traffic channel. However, all the remote units that share the traffic channel can store this soft handoff information and later use the information to initiate soft handoffs without needing to exchange handoff messaging with the base site. Thus, a CDMA-dispatch, shared-channel implementation is enabled by providing soft handoff signaling windows and the over-the-air, soft-handoff messaging required for dispatch services is reduced.

Method and apparatus for CDMA soft handoff for dispatch group members

A CDMA base site provides dispatch group call service to members of a dispatch group by using a first long-code mask. The base site also repeatedly transmits the group call's channel assignment so that a scanning communication unit can detect that the call is active. In order for the scanning communication unit to decode the dispatch communication once the call is detected, it requests a long-code mask transition from the base site. The base site then transmits a new long-code mask and begins encoding the dispatch communication using the new mask. Thus, the scanning communication unit is able decode the communication and thereby join the active CDMA dispatch group call.

Method and apparatus for providing dispatch scan in a CDMA communication system

A multi-site communication system (100) includes a plurality of communication units ( 112-117), a central controller (101) for coupling a plurality of communication sites (106-108), and a site controller (103) corresponding to one of the communication sites (106). Communication access between two or more communication units (112-117) can be enhanced by a method (200, 300) including the steps of receiving (201) a request for a first communication, and directing (211) the appropriate site controller to re-submit the request. By so doing, the site controller (103) can request (314) the central controller (101) to establish a realizable communication between two communication units in the system (113, 114).

Method for enhancing communication access in a radio communication system

A radio communication system controller (100) includes a first (103) and second (104) processor for processing input communication messages (101) used in a radio communication system. The controller (100) further includes shared memory (105), which memory is accessible to each of the first (103) and second (104) processors, for storing the input communication messages (101). The controller (100) is further equipped with fault detection capability (107) for determining (402) when a processing fault has occurred.

Apparatus for providing fault tolerance in a radio communication system

A method of collapsing a communication path among at least two communication units (104-107) reduces the number of sites normally required to provide a communication. Each of a plurality of site controllers (103) in a radio communications system has a corresponding coverage area (100, 101), and at least some of the coverage areas (710-712) overlap one another. The method includes the step of determining (402) whether the communication units are currently being serviced by different sites, and then determining (405) whether they can be serviced by a common site. When the communication units are serviceable by a common site, the call might be established (406) through the common site, resulting in a reduced number of sites required to complete a call.

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Buffalo Grove, IL, United States of America

Alexander Rozenstrauch