Abstract: Binding proxies are used to reduce packet routing delays and call setup delays in a data network made up of a plurality of subnetworks. The binding proxy detects when a mobile device connects to a subnetwork and sends a binding message to various correspondent device(s) in the data network. The binding message contains a care-of-address of the mobile device that allowing the correspondent device(s) to send messages directly to the subnetwork that the mobile device is connected, thereby bypassing a home agent of the mobile device.

Abstract: A wireless multi-carrier communication system having designated control sub-channels (402) that enable a receiving device (106) to operate in a low power decoding mode. A sending device (104) may send control or payload information via the control sub-channels. The receiving device (106) operates in a low-power decoding mode to decode the control sub-channels, yielding the control or payload information. If the sending device has payload information directed to the receiving device that can not fit within the control sub-channels, it sends the information to the receiving device in one or more payload sub-channels (404). The receiving device operates in a second, generally higher power decoding mode to decode the payload sub-channels, yielding the payload information.

Abstract: A communication system (200) wherein time slots are divided into subslots by dividing the time slots at least in frequency. These subslots are used to efficiently transmit small amounts of data. For wide bandwidth signals, dividing time slots in frequency is more efficient than dividing time slots only in time because of the fixed overhead per time slot needed for propagation delays and time synchronization. The division of time slots into subslots can reduce the probability of collisions of random access transmissions by providing more random access opportunities. In an alternate embodiment, communication units (210) making random access transmissions transmit in multiple subslots of time slots to increase the probability that at least one transmission will not experience a collision.

Abstract: A packet-based, multimedia communication system is disclosed that extends IP host functionality to wireless terminals serviced by wireless links. A service controller of the communication system manages communications services such as voice calls, video calls, web browsing, video-conferencing and/or internet communications over a wireless packet network between source and destination host devices. A multimedia content server of the communication system provides access to one or more requested multimedia communication services. A bandwidth manager of the communication system determines an availability of bandwidth for the service requests and, if bandwidth is available, reserves bandwidth sufficient to support the service requests. Wireless link manager(s) of the communication system manage wireless communication resources required to support the service requests.

Abstract: A radio frequency communications system (100) includes wireless terminals (102) and base sites (104). The wireless terminals communicate with the base sites over a radio frequency channel (106). The base sites are interconnected to each other and other network elements via a packet network. The communication system has a radio frequency channel (400) with time slots (406, 408) for transmission of both delay-sensitive data, such as streaming audio and video, and non-delay-sensitive data. A method and apparatus are provided for determining whether a time slot in the radio frequency channel is to be allocated to delay-sensitive data or non-delay-sensitive data (704, 706, 708). Each packet of data transmitted over the wireless channel has a type of service field (900). The type of service field has a precedence or priority value (902) and a service type (904).

Abstract: A slot format and acknowledgment method for use in a communication network that contains one or more wireless links. The slot format provides for the segmenting and reassembly of packets for transport over a wireless link. It also provides support for multiple types of service for the data being carried over the wireless link as well as allocating of access to the wireless link among a plurality of communication units. The acknowledgment method provides for detection of errors over the wireless link, the selective acknowledgment of error-free transmissions and the selective resending of transmissions received in error.

Abstract: A radio frequency communications system (100) includes wireless terminals (102) and base sites (104). The wireless terminals communicate with the base sites over a radio frequency channel (106). The base sites are interconnected to each other and other network elements via a packet network. A method and apparatus determine for a particular delay-sensitive application on the wireless terminal, for example, an audio or video transmission, the requirements for bandwidth for transmission over the radio frequency channel (500, 502). After the requirements on the radio frequency channel are determined, the necessary channel bandwidth, if available, is reserved or allocated to guarantee performance to the application (510). The reserved bandwidth is utilized by selectively granting access to the radio frequency channel on the basis of the bandwidth allocated to the device.

Abstract: A scalable slot format defining positions of synchronization symbols, pilot symbols and data symbols for various numbers of sub-channels and various lengths of time in a multi-carrier communication system. An initial pattern (500) and one or more follow-on patterns (600, 700) are defined identifying positions of data symbols, synchronization symbols and pilot symbols for a first number of sub-channels corresponding to a first bandwidth. An extended pattern is constructed from the one or more follow-on patterns. The extension pattern is appended to the initial pattern to from a base pattern (810, 910, 1010). The base pattern (810, 910, 1010) is replicated zero or more times to form an expanded pattern (812, 910, 1015) identifying positions of data symbols, synchronization symbols and pilot symbols for an expanded number of sub-channels corresponding to a second bandwidth.

Abstract: A message transmission queue (300) including a high priority queue (HPQ) (301) having a high priority entry point; a medium priority queue (MPQ) (303) having a medium priority entry point; and a low priority queue (LPQ) (305) having a low priority entry point. Messages in the MPQ (303) are queued after all messages in the HPQ (301). Messages in the LPQ (305) are queued after all messages in the MPQ (303). A sequencer reinserts messages into the queue (300) based on the message repeat count and the message's previous queue position.

Abstract: A method and apparatus for mitigating data congestion in a radio communication system makes use of a data controller that provides a data buffer for storing data messages to be transmitted over a common communication resource. If the stored data messages cannot be favorably transmitted on the common communication resource, the data controller transmits a congestion indication message over the common communication resource to a plurality of communication devices. In this manner, transmission activity is limited at the communication device, thereby allowing for data traffic to be transmitted.

Abstract: A first communication device (e.g., 103), which includes an unsuccessful transmission attempt counter (203) and an information transmitter (207), provides information to a second communication device (e.g., 105) in the following manner. The first communication device transmits information to the second communication device. The first communication device then determines whether the second communication device received at least a portion of the information. When the second communication device has not received at least the portion of the information to produce an unsuccessful transmission attempt, the first communication device determines whether a quantity of unsuccessful transmission attempts is less than a first threshold value. When the quantity of unsuccessful transmission attempts is less than the first threshold value, the first communication device retransmits the information to the second communication device.

Abstract: An APCO 25 radio communication system 200 includes a repeater 101 arranged to receive signals from an inbound repeater link 103, thereby forming received signals. The repeater 101 is arranged to forward the received signals to a subscriber 121 via an outbound radio frequency path 113. The received signals include two types of packets, namely, packets 105 with correctable errors 107, and "erasure packets"109 with detectable-but-uncorrectable errors 111. The inbound repeater link is equipped with error correcting means 110 for correcting the correctable errors 107. The inbound repeater link is also equipped with error mitigating means 130 for mitigating the detectable-but-uncorrectable errors 111. The error mitigation is performed in accordance with the improved multi-band excitation ("IMBE") process.

Abstract: In a modulator (300), a symbol weight determiner (301) determines a scaling factor (310) for at least one symbol (308). An integrator (303) and a complex symbol generator (305) operate to produce at least one complex symbol (314) based on the at least one symbol. The scaling factor (310) is used to scale the at least one complex symbol. In one embodiment, a scaler (307) comprises a gain-modifiable amplifier (609) and, in a second embodiment, the scaler comprises a gain-modifiable filter (809). When such a modulator is incorporated into an RF communication device (600, 800), the energy used to transmit any given symbol can be varied according to the relative importance of that symbol. Additionally, the overall received sensitivity of a communication, at a given signal strength, can be improved.

Abstract: Delayed symbols (204), including a current symbol (205), are compared by a comparator (206) with at least one predetermined pattern when the current symbol is equivalent to one of a set of predetermined values. Alternatively, a sign of the current symbol is compared with signs of a previous and a subsequent symbol when the current symbol is equivalent to one of the set of predetermined values. When the current symbol is equivalent to one of the set of predetermined values and when either the delayed symbols are equivalent to one of the at least one predetermined pattern or the sign of the current symbol matches the signs of the previous and subsequent symbols, a symbol corrector (208) applies a predetermined function to the current symbol to produce a received symbol (210).

Abstract: In a digital communication system, communication units may reduce power consumption while attempting to detect reception of valid data by sampling and filtering a data stream at a first sampling rate producing a first filtered data stream. When the first filtered data stream indicates potential valid data, the communication unit samples and filters the data stream at a second sampling rate, wherein the second sampling rate is greater than the first sampling rate and consumes more power, producing a second filtered data stream. The communication unit determines whether the data stream contains valid data based on the second filtered data stream.

Abstract: An uncorrectable set of input vectors (303), comprising a primary input vector (P) and a secondary set of input vectors (S), is provided at a sender (301). The secondary set of input vectors is error correction encoded and modulated with a predetermined input vector (PIV) to produce a secondary set of modulated vectors (S'). A predetermined codeword (PC) is sent along with the secondary set of modulated vectors to a target (302). At the target, the predetermined codeword is decoded and the resulting decoded predetermined codeword 306 is used to demodulate the secondary set of modulated vectors. As the predetermined codeword is chosen such that, when decoded, it is not identical to the predetermined input vector, the secondary set of demodulated vectors (S") will contain a sufficient number of errors to indicate to the target that the set of input vectors is uncorrectable.

Abstract: Communication units are provided access to a communication system (100) in the following manner. A base station (202) receives, from a requesting communication unit, a request, via a shared inbound communication resource (209), for an available message path (207). When a dual-mode outbound communication resource is operating in a control mode (205), the message path (207), having a first inbound communication resource (204) and the dual-mode outbound communication resource operating in a partial control mode (206), is assigned to the requesting communication unit. Thus, the shared inbound communication resource is consistently available, providing access to the communication system.

Abstract: An FM receiver (100) that includes a plurality of filtering elements (120-124) that have various center frequencies and bandwidths that adjust to maximize the signal quality of a desired signal (104) recovers the desired signal (104) by inputting the desired signal (104) to each of the plurality of filtering elements (120-124). Signal recovery is performed on an output of each of the filtering elements (120-124) to obtain a plurality of recovered signals. The recovered signals are then measured to obtain a plurality of signal quality metrics for the desired signal.

Abstract: Within a fixed infrastructure of a communication system, message portions of code words that are found to be uncorrectable (erasures) are transmitted with a predetermined number of bits in place of the parity portion associated with those code words. These predetermined number of bits indicate the existence of the erasures, which can be reproduced for continued transmission to the final destination. By having the number of predetermined bits being less than the number of parity bits, the bandwidth requirement for wireline communication paths is reduced.

Abstract: Discrete packets (306) containing encoded voice information are transmitted within frames (301 and 302) in a repetitive manner until all voice information has been sent. Following transmission of all packets containing such voice information, at least a predetermined number of additional packets (401) are then transmitted, which additional packets represent silence. Following this, a disconnect signal (304) is transmitted. So configured, loss of the disconnect signal due to fading or other communication pathway disturbances will not necessarily lead to audibilization of undesired sounds, as the decoding protocol at the receiver (200) provides for reprocessing of recently received packet information in the absence of newly available reliable information. Hence, the silence information is continually reprocessed until either reliable information is again available or a time out sequence concludes.