Abstract: Technologies directed to scheduling transmissions between a satellite system and customer terminals (CTs) with half-duplex (HD) radios are described. A communication system includes a radio, a modem with a HD controller, a downlink (DL) scheduler, and an uplink (UL) scheduler. The HD controller determines a first set of HD CTs that are eligible DL transmissions for a first radio frame and a second set of HD CTs that are eligible for UL transmissions for a second radio frame. The HD controller determines a throughput value and buffer information about each of the first set and the second set of HD CTs. The HD controller determines a first subset of HD CTs for DL scheduling and a second subset of HD CTs for UL scheduling. The DL scheduler schedules radio resources for a first radio frame and the UL scheduler schedules radio resources for a second radio frame.

Abstract: A satellite provides communication between user terminals (UTs) and ground stations that connect to other networks, such as the Internet. Because the satellite is within range of many UTs at any given time, many UTs are in contention to use an uplink to send data to the satellite. Each satellite manages uplink contention by maintaining state data representative of the uplink resources allocated for use. As satellites move, handovers take place, transferring communication services from a first satellite to a second satellite. Before a handover, a first satellite sends state data to a UT. The second satellite is also informed about the UT. After the handover, the second satellite provides the UT with priority access to the uplink to send the state data to the second satellite. The second satellite uses the state data to resume management of the uplink, eliminating the need for time consuming link setup.

Abstract: Techniques for improving the efficiency of transmitting data between devices are described. In an example, a first device transmits first data to a second device during a first time interval, whereby the second device is configured to communicate with the first device in a half-duplex mode. During a second time interval, the first device receives second data from the second device. The first device then determines that the second device transmitted the second data during a third time interval that is between the first time and the second time, and during which a reception of the first data by the second device is expected. The first device then retransmits the first data based at least in part on determining that the second device transmitted the second data during the third time interval.

Abstract: A satellite provides communication between user terminals (UTs) and ground stations that connect to other networks, such as the Internet. Because the satellite is within range of many UTs at any given time, many UTs are in contention to use an uplink to send data to the satellite. Each satellite manages uplink contention by maintaining state data representative of the uplink resources allocated for use. As satellites move, handovers take place, transferring communication services from a first satellite to a second satellite. Before a handover, a first satellite sends state data to a UT. The second satellite is also informed about the UT. After the handover, the second satellite provides the UT with priority access to the uplink to send the state data to the second satellite. The second satellite uses the state data to resume management of the uplink, eliminating the need for time consuming link setup.

Abstract: A satellite provides communication between user terminals (UTs) and ground stations that connect to other networks, such as the Internet. Because the satellite is within range of many UTs at any given time, many UTs are in contention to use an uplink to send upstream data to the satellite. Contention for the uplink may be managed by sending grants that allocate a portion of the uplink time and frequency resources to individual UTs. A UT serviced by the satellite uses information based on the grants to determine whether upstream data from a user device connected the UT should be accepted for future transmission promised to deliver specified quality of service to the user device. Acting as a distributed system, each UT may decide to approve upstream data based on one or more factors, such as source address, destination address, header flags, predicted radio availability, and so forth.

Abstract: Satellites provide communication between devices such as user terminals and gateways to other networks, such as the Internet. Non-geosynchronous orbit satellites move relative to terrestrial user terminals, passing in and out of communication over time. To maintain ongoing communication, a handover takes place in which the responsibility to maintain communication with a particular user terminal passes from one satellite to another. To minimize disruption due to the handover, satellite motion and availability of communication resources are allocated in advance. Participating devices such as the user terminal, current satellite, and next satellite, are provided with details of the handover in advance. As a result, interruption in communication due to a handover from one satellite to another is substantially reduced.

Abstract: Satellites provide communication between devices such as user terminals (UTs) and ground stations that are in turn connected to other networks, such as the Internet. Latency for signals to and from the satellite can introduce delays due at least in part to propagation time. The latency adversely interacts with data transfers that result in responses from the UT. Downstream data to the UT is processed to determine if a response is expected. Header data is associated with the downstream data that is sent to the satellite. A resource scheduler onboard the satellite uses the header data to provide a prospective grant to the UT to send the expected response. The UT receives the downstream data, response data such as an acknowledgement is generated, and the response data is sent to the satellite using the prospective grant. The system substantially reduces the latency associated with responsive traffic and improves overall throughput.

Abstract: Satellites provide communication between devices such as user terminals and gateways to other networks, such as the Internet. Non-geosynchronous orbit satellites move relative to user terminals, passing in and out of communication over time. The user terminal itself may also move. Each satellite maintains a plurality of subbeams, each directed towards a different area on the Earth for a portion of an orbit. Based on a predicted location for the user terminal, a handover from a first subbeam to a second subbeam is determined. To minimize disruption due to the handover, communication resources associated with the second subbeam are allocated and provided to the user terminal and the satellite in advance. At the handover time, if the user terminal is within a threshold distance of the predicted location, the user terminal may transition to using the second subbeam. Otherwise, the user terminal may continue to use the first subbeam.

Abstract: The method for handover at user equipment includes decoding an information block from at least one of one or more target base stations before receiving a handover command indicating to handover to a first target base station and connecting to the first target base station using the decoded information block.

Abstract: A method of adjusting a power level of communications over a channel in a wireless communications network. In the method, a determination (e.g., by a radio network controller (RNC)) is made regarding a number of base stations actively communicating with a mobile station. For example, the determination may indicate whether the mobile station is engaged in soft handoff or simplex mode. One of a plurality of power control algorithms (e.g., a fixed offset power control algorithm, a channel quality indicator (CQI) power control algorithm, etc.) is selected based on the determination. A power level of communications over the channel (e.g., a downlink communications channel to the mobile station) is then adjusted in accordance with the selected power control algorithm.

Abstract: A wireless communication network (20) utilizes a hard handoff procedure for switching between cells serving a mobile station (40). In a disclosed example, the existing link between the mobile station (40) and a serving base station (38) is not released until a new link between a target base station (32) and a mobile station (40) is established. At the same time, however, the mobile station maintains only one base station or link within its active set at all times. The disclosed example is useful for dedicated channel and shared channel communications in CDMA systems, for example.

Abstract: A method of processing, in parallel fashion, messages from a User Equipment (UE) in soft handoff with a plurality of base stations of a wireless communication system. Measurement Messages from the User Equipment are received and stored in a message buffer for a defined period of time. Later arriving messages replace previous messages during the defined period of time. When the defined period of time elapses, the latest stored message is processed in parallel fashion in a processing pipeline with other messages for the UE and other UEs. The latest message is processed by first converting it to soft handoff actions and inserting such actions into a processing pipeline. A conflict table is generated during the parallel processing of the soft handoff actions to avoid the processing of messages that conflict with each other. Conflicting messages are put into a pending state and remain in such state until they are canceled by subsequent messages or the conflict no longer exists.

Abstract: A method of adjusting a power level of communications over a channel in a wireless communications network. In the method, a determination (e.g., by a radio network controller (RNC)) is made regarding a number of base stations actively communicating with a mobile station. For example, the determination may indicate whether the mobile station is engaged in soft handoff or simplex mode. One of a plurality of power control algorithms (e.g., a fixed offset power control algorithm, a channel quality indicator (CQI) power control algorithm, etc.) is selected based on the determination. A power level of communications over the channel (e.g., a downlink communications channel to the mobile station) is then adjusted in accordance with the selected power control algorithm.

Abstract: A wireless communication network (20) includes a power management module (50) for controlling the power of transmission between a base station (38) and a mobile station (40). Bearer traffic (e.g., voice or data signals) are transmitted using a first transmission power limit. Handoff messages are transmitted using a second, higher transmission power limit. In one example, the power management module (50) selects an increment to the first transmission power limit for purposes of transmitting handoff signals.

Abstract: A wireless communication network (20) utilizes a hard handoff procedure for switching between cells serving a mobile station (40). In a disclosed example, the existing link between the mobile station (40) and a serving base station (38) is not released until a new link between a target base station (32) and a mobile station (40) is established. At the same time, however, the mobile station maintains only one base station or link within its active set at all times. The disclosed example is useful for dedicated channel and shared channel communications in CDMA systems, for example.

Abstract: In a method of detecting a mobile station that is not following a power control command, for each time slot, a received signal-to-interference ratio (SIR) value of the mobile as measured by a given base station is compared with a given average SIR target value. An error metric may be generated for each slot based on a difference between the measured SIR and average SIR target values. The generated error metrics may be averaged over a given time duration to determine at least one (or more) average error value(s), and the mobile station is determined as violating a power control command if the at least one or more average error value(s) exceed a given threshold.

Abstract: A wireless communication network (20) utilizes a down bias to minimize or eliminate random walk when controlling a transmit power between a base station (38) and a mobile station (40). In a disclosed example, a link quality monitoring module (54) determines the quality of a link between the mobile station (40) and the base station (38). A power control module (52) applies a down bias, which is dependent on the determined link quality, to a transmit power correction for minimizing random walk. In a disclosed example, the down bias varies linearly and inversely proportionally to the quality of the link between the mobile station and the base station.

Abstract: A method of processing, in parallel fashion, messages from a User Equipment (UE) in soft handoff with a plurality of base stations of a wireless communication system. Measurement Messages from the User Equipment are received and stored in a message buffer for a defined period of time. Later arriving messages replace previous messages during the defined period of time. When the defined period of time elapses, the latest stored message is processed in parallel fashion in a processing pipeline with other messages for the UE and other UEs. The latest message is processed by first converting it to soft handoff actions and inserting such actions into a processing pipeline. A conflict table is generated during the parallel processing of the soft handoff actions to avoid the processing of messages that conflict with each other. Conflicting messages are put into a pending state and remain in such state until they are canceled by subsequent messages or the conflict no longer exists.