Telefonaktiebolaget Lm Ericsson (publ)

Sylvain Labonte

Eric Turcotte

Francois Sawyer

Richard Joseph Brunner

Francis Lupien

Michel Desgagne

Pat Minichiello

Sylvain St-Pierre

Gopichand Kongara

A cellular communications network includes a plurality of cells whose base stations have both sector and smart antenna capabilities. While engaged in a call, mobile station downlink signal strength measurements are made on its own serving traffic channel and the control channels of neighboring cells. These measurements are then adjusted by one or more factors which take into account the operational and physical differences between sector antenna and smart antenna. For example, the signal strength measurements may be appropriately adjusted by measured differences in gain between the smart antenna and sector antenna, output power backoff values associated with smart antenna and sector antenna support of the traffic channels in comparison to the control channels, and power control attenuation applied to the traffic channels. The resulting adjusted downlink signal strength measurements may then be compared against each other (as off-set by any imposed hysteresis value) to more precisely locate the mobile station and uniformly, predictably and accurately identify when it is appropriate to authorize a hand-off.

Preservation of cell borders at hand-off within a smart antenna cellular system

There is disclosed a prepaid system and method for permitting a prepaid subscriber of the cellular wireless telecommunication system to revise call features during a call within the operators node and from roaming locations to debit the subscribers prepaid account on a real-time basis. The system includes a switching node permitting a call to be set up with the prepaid subscriber when a prepaid service credit balance exists and terminating the call when the prepaid service credit balance is nil. The switching node continually generates real-time call event Date Message Handler (DMH) formatted messages related to the call made by the prepaid subscriber and forwards these call event messages to a prepaid administrative network. The prepaid administrative network stores the prepaid service credit balance of the prepaid subscriber and generates at call set up an initial charge debiting rate used during the call to reduce the prepaid service credit balance. The prepaid administrative network, in response to the real-time call event messages received from the detailed call event generation means, revises the initial charge debiting rate to generate a real-time debiting rate used during the call to reduce the prepaid service credit balance.

Wireless telecommunication system with prepaid architecture

A system for determining when a radio telecommunications network should switch between a first grade of service and a second grade of service based upon a highly accurate and reliable estimate of the bit error rate (BER). The system estimates the BER on an uplink and a downlink on a user channel, and determines whether the BER on the uplink and the downlink on the user channel are below a first set of thresholds. The system then measures the residual BER (RBER) and the frame erasure rate (FER) on the voice channel uplink, and determines whether the downlink BER, the uplink RBER, and the uplink FER are lower than a second set of thresholds. If lower, the system sends and receives a data message on a Fast Associated Control Channel (FACCH). The system obtains a highly accurate estimate of the BER on a downlink on the FACCH channel, and reports the downlink BER in a message on the FACCH channel uplink. The system then estimates the BER on the FACCH channel uplink. Finally, the system switches the radio telecommunications network from the first grade of service to the second grade of service in response to determining that the uplink and downlink BER on the FACCH channel are below a third set of thresholds.

Estimation of radio channel bit error rate in a digital radio

A D-AMPS+ cellular communications air interface is presented wherein a packet data control channel and packet data traffic channel is supported in addition to the conventional digital control channel and digital traffic channel. In particular, the packet data control channel, packet data traffic channel and digital traffic channel support multiple modulation level operation (high versus low). Procedures are provided for intracell and intercell modulation transition of mobile station communications carried by a traffic channel. In particular, these procedures facilitate intracell and intercell modulation transition to a traffic channel using the same level of modulation, as well as intracell and intercell (fall-forward and fall-backward) modulation transition to a traffic channel using a different level of modulation.

Support of multiple modulation levels for a cellular traffic channel

A D-AMPS+ cellular communications air interface is presented wherein a packet data control channel and packet data traffic channel is supported in addition to the conventional digital control channel and digital traffic channel. In particular, the packet data control channel and packet data traffic channel support multiple modulation level operation (high versus low). Procedures are provided for mobile station selection, as well as re-selection, of either the high or low-level modulation for the packet channels. Procedures are further provided for facilitating a fall-forward to the high-level modulation packet data control channel, or a fall-backward to the low-level modulation packet data control channel with respect to both uplink and downlink packet data communications.

Growing community of inventors

St-Bruno de Montarville, Canada

Sylvain Labonte