Abstract:
Collisions between messages simultaneously transmitted by multiple spread spectrum transmitters are reduced by distributing the transmissions over the available resources of the receiver. Each mobile station uses one or more randomization methods to distribute its transmissions. Each mobile station includes a microprocessor (100); an encoder (140); a timing generator (136); a PN long code sequence generator (146); and XOR gate (152). The system is used in a CDMA mobile telephone system.
Abstract:
A network operator identifier is used to uniquely identify each network operator to support international roaming. The network operator identifier includes (1) a Mobile Country Code (MCC) that identifies the country in which a network operator belongs and (2) a Network Operator Code (NOC), which may be a Mobile Network Code (MNC), that distinguishes network operators within a given MCC. Each network operator is assigned a unique combination of MCC and NOC that distinctly identifies the network operator, and the network operator identifier can be stored in a single entry in a preferred roaming list. The base stations of each network operator broadcast the network operator identifier in signaling messages. A mobile station receives a signaling message from a base station, obtains the network operator identifier, searches its preferred roaming list for an entry with the network operator identifier, and determines whether or not the current CDMA network is accessible.
Abstract:
A method for coherent estimation of the traffic-to-pilot energy ratio is presented. A received preamble is decoded (20), and then re-encoded (22). The received preamble is then multiplied by the re-encoded preamble (23). The results are summmed (24), squared (26), and then divided by a pilot energy value (28). In another method, a message (41) carrying energy information can be inserted between a subpacket preamble (40) and a subpacket (42).
Abstract:
A method and apparatus for coordinating the time at which a mobile station (5) performs searches for alternative systems to which a hard handoff will occur. In one system which includes the present invention, the mobile station (5) receives a command which instructs the mobile station (5) as to when to tune to alternative frequencies in order to search for indications of the presence of an alternative system. In another system which includes the present invention, predetermined times are defined with respect to a reference point in time that is common to both an origination base station (10) and a mobile station (5). The mobile station (5) tunes to alternative frequencies to perform searches only during these predetermined times. In addition, the mobile station (5) coordinates the transmission of reports which indicate the results of searches for alternative systems such that these reports are only transmitted from the mobile station (5) when the mobile station (5) is tuned to the origination frequency.
Abstract:
A method for a base station is disclosed for controlling the transmission energy of forward link signals comprising the steps of receiving a potentially gated reverse link signal including forward link power control bits, determining whether said power control bits have been gated out, and adjusting forward link transmission energy in accordance with said forward link power control bits only when said determination as to whether said forward link power control bits have been gated out indicates that said power control bits have not been gated out.
Abstract:
Aparato para su uso en una estación móvil en un sistema de comunicación inalámbrica, comprendiendo el aparato: un primer medio para detectar si las tramas recibidas desde una estación base son correctas o defectuosas; un segundo medio (224) para contar las tramas defectuosas recibidas; un tercer medio (226) para contar las tramas correctas recibidas; un cuarto medio para reiniciar el segundo medio (224) en cero e incrementar el tercer medio (226) en uno si una trama recibida se declara como trama correcta, y para incrementar el segundo medio (224) en uno y reiniciar el tercer medio (226) en cero si una trama recibida se declara como una trama defectuosa, y para inhabilitar un transmisor si el valor del segundo medio (224) alcanza un umbral predeterminado.
Abstract:
Un procedimiento para proporcionar un mensaje de radiodifusión en un sistema de comunicaciones inalámbricas que emplea radiomensajería en ranuras de tiempo, asignando el sistema una pluralidad de canales de radiomensajería para transmitir radiomensajes en el sistema, comprendiendo el procedimiento: transmitir de forma periódica un radiomensaje de radiodifusión en al menos uno de la pluralidad de canales de radiomensajería, anunciando el radiomensaje de radiodifusión un mensaje de radiodifusión; transmitir un indicador de nuevo radiomensaje en cada ranura de tiempo en un ciclo de máxima ranura de tiempo en la pluralidad de canales de radiomensajería para indicar si va a transmitirse un nuevo radiomensaje de radiodifusión; transmitir el nuevo radiomensaje de radiodifusión en al menos uno de la pluralidad de canales de radiomensajería; y transmitir el mensaje de radiodifusión en una posición de ranura de tiempo indicada por el nuevo radiomensaje de radiodifusión.
Abstract:
Apparatus and method for use in a mobile station in a wireless communication system, comprising in which: a decoder (218) detects if frames received from a base station are good or bad; a first counter (224) counts received bad frames; a second counter (226) counts received good frames; a control processor for resets the first counter (224) to zero and incrementing the second counter (226) by one if a received frame is declared a good frame, and incremens the first counter (224) by one and resetting the second counter (226) to zero if a received frame is declared a bad frame, and disables a transmitter if the value of the first counter (224) reaches a predetermined threshold.