Abstract: A method and apparatus for reducing transmission delay in a wireless communication system that carries packetized voice and data information. Interruptions in the traffic channels cause loss of synchronization between a header compressor and a header decompressor. Rather than transmitting resynchronization information on the traffic channel, the information dropped by an interruption is re-transmitted on a non-traffic channel in parallel with the traffic channel. At the remote station, information from the traffic channel and the non-traffic channel is reassembled before input into the decompressor. Alternatively, the non-traffic channel can be used to carry overflow information so that a higher average data rate can be achieved than the average data rate of the traffic channel alone.

Abstract: A method and apparatus for providing frame re-transmission in a broadcast communication system. Frame re-transmission is accomplished only when a predetermined number of negative acknowledgement messages are received with respect to one or more data frames. The predetermined number may vary in accordance with various operating parameters, such as the latency of the transmission and/or the number of wireless communication devices currently receiving a broadcast transmission.

Abstract: Techniques for supporting IP framing with lower computational load are disclosed herein. In one aspect, IP packets are partitioned into RLP frames. Subsequently, the IP packets, partitioned into RLP frames, are transmitted on a wireless data link employing RLP. In another aspect, received RLP frames are reconstructed into IP packets. The RLP framing is used to supply frame boundaries for the reconstructed IP packets. These aspects have the benefit of using the underlying frame transmission and framing properties of RLP, thus minimizing computational load associated with framing, transmitting, and receiving IP packets. The techniques described herein apply equally to both access points and access terminals.

Abstract: In a half-duplex communication system in which additional delays in the communication channel may cause a message collision between a message and a response, a collision detector is utilized to prevent and detect message collisions. The collision detector determines if a response may be transmitted from the communication device while it is receiving the current message. If no response is expected, the collision detector is placed into a train mode. If a response is possible, the collision detector is placed into the monitor mode. In the monitor mode, the collision detector monitors the communication channel and determines if a message collision has occurred during transmission of the message. A detection of a message collision causes retransmission of the message or possibly a new message at a later time after it has been determined that the communication channel is clear.

Abstract: A method and apparatus for resolving ambiguity in reception of multiple retransmitted frames includes ascertaining for each data frame received from a transmitter whether the frame is a retransmitted frame. If the frame is a retransmitted frame, the frame may be stored in a resequencing buffer. If an abort timer associated with the second round of retransmission has been set for the retransmitted frame, an associated negative-acknowledgment-list (NAK-list) entry is not removed from a NAK list until the abort timer has expired. If the abort timer has not been set for the retransmitted frame, the associated NAK-list entry is removed from the NAK list. The method and apparatus may reside in a transport function in which a transmitter sends data frames to a receiver in accordance with the Radio Link Protocol interface. The transport function may reside in, e.g., a data-capable cellular or satellite-based base station and subscriber unit.

Abstract: Method and apparatus for providing an overhead information for a broadcast service in a wireless communication system via an out-of-band transmission. The mobile station is able to contact the content server directly using the out-of-band-signaling over a packet data service option. The out-of-band communication allows the content server to update the information without transmitting via an intermediate infrastructure element. In one embodiment, the overhead information includes a service option number corresponding to a set of broadcast parameters, such as those identifying a protocol stack for processing broadcast content.

Abstract: Method and apparatus for providing broadcast overhead information interleaved with a broadcast session in a transmission on a broadcast channel of a wireless communication system. In one embodiment, the information is stored at the receiver to provide quick updating when a user changes to an alternate broadcast channel. In one embodiment, the content server provides an identifier SDP_ID to distinguish among sets of protocol options description sets.

Abstract: Methods and apparatus for providing broadcast overhead information interleaved with a broadcast session in a transmission on a broadcast channel of a wireless communication system. In one embodiment, the information identifies parameters and a protocol stack for processing broadcast content. In one embodiment, the information is stored at the receiver to provide quick updating when a user changes to an alternate broadcast channel.

Abstract: A method and apparatus for resolving ambiguity in reception of multiple retransmitted frames includes ascertaining for each data frame received from a transmitter whether the frame is a retransmitted frame. If the frame is a retransmitted frame, the frame may be stored in a resequencing buffer. If an abort timer associated with the second round of retransmission has been set for the retransmitted frame, an associated negative-acknowledgment-list (NAK-list) entry is not removed from a NAK list until the abort timer has expired. If the abort timer has not been set for the retransmitted frame, the associated NAK-list entry is removed from the NAK list. The method and apparatus may reside in a transport function in which a transmitter sends data frames to a receiver in accordance with the Radio Link Protocol interface. The transport function may reside in, e.g., a data-capable cellular or satellite-based base station and subscriber unit.

Abstract: A 32 bit digital “amended electronic serial number” (AESN) is generated from a 56 bit “extended electronic serial number” (EESN). The AESN distinguishes each subscriber unit within a wireless system from each other subscriber unit. Two distinct methods are disclosed. In the first method, a manufacturers code field (“MFR”) is tested to determine whether the subscriber unit has been assigned an EESN. If so, then the least significant 8 bits of the manufacturer's code field (“EMFR”) are appended to the “serial number” field (“SN”). In the second method, each manufacturer generates serial numbers by applying a pseudo-random sequence. The “seed” for the pseudo-random sequence is based on the manufacturer's EMFR. This serial number is then combined with the 8 bit MFR.

Abstract: A method for detecting delayed data frames in a transport function includes the steps of comparing a frame sequence counter with a predetermined threshold value, detecting a delayed frame if the sequence counter exceeds the threshold value, and processing the detected delayed frame accordingly. In an RLP data transport protocol, the delayed frame may be processed as a retransmitted frame. The threshold value may be proportional to the maximum number of frames sent in a given bundle times the maximum delay, in units of frame intervals, between frames sent simultaneously over the air in the same frame interval.

Abstract: Apparatus and methods for supporting analog fax calls between two wireless subscriber stations in a tandem configuration are presented herein. To support the tandem configuration, full duplex communication may be established between the two base stations. Full duplex communication may be realized by incorporating an echo canceler in the base station, or by utilizing both BFSK channels of the V.21 fax system for communication. The tandem configuration may also be supported by advanced flag synchronization, wherein a second base station will immediately start sending preamble flags to a first base station after a message is transmitted from the first base station to the second base station. The first base station may then synchronize its receiver for immediate receipt of the return message from the second base station.

Abstract: A method for detecting delayed data frames in a transport function includes the steps of comparing a frame sequence counter with a predetermined threshold value, detecting a delayed frame if the sequence counter exceeds the threshold value, and processing the detected delayed frame accordingly. In an RLP data transport protocol, the delayed frame may be processed as a retransmitted frame. The threshold value may be proportional to the maximum number of frames sent in a given bundle times the maximum delay, in units of frame intervals, between frames sent simultaneously over the air in the same frame interval.

Abstract: The present invention provides an apparatus and method for supporting analog fax calls between two wireless subscriber stations in a tandem configuration. The existence of a tandem configuration is detected, and a more efficient communication protocol is established between two base stations upon detection of the tandem configuration. A message generator in a first base station generates an identification message. If the identification message is received by a second base station, the second base station will be informed that the tandem configuration exists. A message generator in a second base station may then generate a return message, which when received by the first base station, will notify the first base station of the existence of the tandem configuration. To support the tandem configuration, full duplex communication may be established between the two base stations.

Abstract: A method and apparatus to facilitate service negotiation by a digital telecommunications system that allows a low activity communication to be transmitted by the system over vocoded channels. In one embodiment, once the telecommunication system is noticed that a low activity signal needs to be transmitted, each telecommunication system vocoder involved in the transmission automatically locks into full rate, and where applicable, adjusts the transmission power to reduce frame error rate. Further, the telecommunications system may include any number of wireless links. The invention includes a noticing apparatus coupled to a sensor that receives a low activity communication device attachment and notices the digital telecommunications system that a low activity communication is being initiated or discontinued.

Abstract: In a half-duplex communication system in which additional delays in the communication channel may cause a message collision between a message and a response, a collision detector is utilized to prevent and detect message collisions. The collision detector determines if a response may be transmitted from the communication device while it is receiving the current message. If no response is expected, the collision detector is placed into a train mode. If a response is possible, the collision detector is placed into the monitor mode. In the monitor mode, the collision detector monitors the communication channel and determines if a message collision has occurred during transmission of the message. A detection of a message collision causes retransmission of the message or possibly a new message at a later time after it has been determined that the communication channel is clear.

Abstract: In a half-duplex communication system in which additional delays in the communication channel may cause a message collision between a message and a response, a timer based collision prevention circuit is utilized to prevent the message collision. The collision prevention circuit determines if the message transmitted by a communication device will be repeated. If the message is to be repeated, the collision prevention circuit sets a countdown collision timer to a predetermined period of time shorter than the shortest repetition interval of the repeated message. A response is only sent to the communication device if the collision timer has not expired. If the timer expires, the collision prevention circuit waits for the message to be retransmitted by the source device before sending the response to the communication device.

Abstract: The present invention provides an apparatus and method for supporting analog fax calls between two wireless subscriber stations in a tandem configuration. The existence of a tandem configuration is detected, and a more efficient communication protocol is established between two base stations upon detection of the tandem configuration. A message generator in a first base station generates an identification message. If the identification message is received by a second base station, the second base station will be informed that the tandem configuration exists. A message generator in a second base station may then generate a return message, which when received by the first base station, will notify the first base station of the existence of the tandem configuration. To support the tandem configuration, full duplex communication may be established between the two base stations.

Abstract: A method and system for detecting fax calls in a network that alternatively operates in either a voice mode or a fax mode. A detection threshold is first initialized, a first detector detects whether a calling tone has been transmitted from a calling fax machine to a called fax machine, and a second detector detects whether an identification tone has been sent from the called fax machine to the calling fax machine. If the calling tone has been transmitted from the calling fax machine to the called fax machine the detection threshold is decremented a first amount, if the identification tone has been transmitted from the called fax machine to the calling fax machine the detection threshold is decremented a second amount, and if both the calling tone and the identification tone have been sent the detection threshold is decremented a third amount. A flag measure is generated by monitoring, with a third detector, signals sent from the called fax machine.

Abstract: A novel and improved method and apparatus for providing an interface to a digital wireless telephone system compatible with standard analog wire line fax machines is described. To process a fax, a source interface waits until an interface to a destination fax machine has been established before establishing an interface to a source fax machine. The source fax transmission rate must be less than or equal to the destination fax transmission rate and the data rate of the digital channel. To establish the source fax interface at the proper rate, the source interface first selects and initial data rate from a set of standard fax transmission rates. The source interface sends unacceptable rate (failure to train) messages to the source fax machine until the source fax transmission rate is less than or equal to the data channel rate and the destination fax transmission rate.