Abstract: An encoding method comprises generating a character map of an alphanumeric character string, identifying runs of like character type symbols in sequential positions, and removing the runs of character type symbols from the character map. The center for the center infix run is determined, and the characters of each character type are encoded into binary encoded substrings. A decoding method comprises parsing the one or more run fields in the alphanumeric header to determine a number of characters of each type of a plurality of character types represented in the binary encoded string, generating a character map having a string of character type symbols representing the binary encoded string, including determining a reduced character map, centering the character type symbols for a center infix run about the center of the reduced character map, completing a final character map, and decoding each binary encoded string.

Abstract: A system and method for transmitting a series of pages in a communication system. The system includes a paging console for placing a plurality of pages in a queue for transmission to one or more targets devices. Each page includes a Dependent-Upon (DU) field that indicates whether the page is dependent upon an earlier page in the queue. Upon initiating a paging event, the plurality of pages are attempted based upon their order in the queue. Prior to transmitting each page, it is determined whether the DU field of that page indicates a dependency upon an earlier page. If there is no dependency, the page is attempted as normal. If the current page is dependent upon an earlier page, a record is checked to determine whether the earlier page was successful. If the earlier page was successful, the current page is attempted. If the earlier page was unsuccessful, the current page is not attempted and is recorded as unsuccessful.

Abstract: The present invention discloses, in a two-way radio frequency (RF) communications system having at least one repeater, a plurality of channels, and a plurality of subscriber units, a repeater receives a message that identifies a channel that is selected to serve as a rest channel for the system. The channel that is currently serving as the rest channel for the system is monitored by subscriber units that are idle in the system. If the repeater determines that the channel selected to serve as the rest channel is hosted by the repeater, the repeater periodically transmits an identity of the channel as the channel currently serving as the rest channel on at least the channel.

Abstract: A method to selectively rendering a communication at a receiving communication device comprises receiving a communication and determining whether an association exists between the receiving communication device and a source of the communication. If an association does not exist between the receiving communication device and the source of the communication, rendering the communication at the receiving communication device or distributing the communication to the receiving communication device in order for the communication to be rendered at the receiving communication device. If an association does exist between the receiving communication device and the source of the communication, preventing the communication from being rendered at the receiving device.

Abstract: Embodiments of the invention relate to a feedback mechanism that informs a user of a communication device to adjust the volume, pitch, tone or other characteristic of his voice so as to compensate for noise in the surrounding environment. The feedback mechanism includes feedback circuitry that analyzes audio signals from the microphone and preferably from one or more additional environmental noise sensors. From the analysis, the feedback circuitry determines characteristics of the user's voice and characteristics of the environmental noise, and provides an analysis of how the user might modify his voice to best compensate for environmental noise. This analysis results in an indication to the user, such as through a vibration, a sound, or graphical indication on the device, which tells the user whether and to what extent the user should adjust a characteristic of his voice to best overcome such environmental noise.

Abstract: A system and method for managing call affiliation in a communication system having a plurality of communication units. When a public call announcement is initiated, a broadcast data message is transmitted to the communication units identifying a public announcement talkgroup for the call. Upon receiving the broadcast data message, each of the communication units waits a random amount of time before attempting to affiliate to the public announcement talkgroup. At the same time, each communication unit also monitors other messages on the control channel. Each communication unit joins the public announcement talkgroup upon the first of either (1) receiving an affiliation grant in response to an affiliation request transmitted by the communication unit, or (2) detecting an affiliation grant being transmitted to a different communication unit attempting to affiliate to the same talkgroup.

Abstract: A system and method for transmitting call information in a communication system having sites with long link delays. Upon a call being initiated within the communication system, a zone controller determines the participating sites that are to be involved in the call and assigns an IP multicast group address for the call. The zone controller also determines whether any of the participating sites have a long link delay. If any of the participating sites do have a long link delay, the zone controller also assigns an IP unicast address for each such site. The call information is then transmitted both on the IP multicast address as well as on each assigned IP unicast address to ensure that the call is received by each participating site without the loss of call information.

Abstract: A system and method for improving the interoperability of communication system components using multiple audio encoding formats within a single talkgroup is provided. The system includes at least two base site repeaters, each of which may be configured to receive and process voice calls from communication units using different audio encoding formats. The system also includes a transcoder provided at either the base sites or as a separate infrastructure server. When a voice call is transmitted to a first repeater using a first audio encoding format, the audio signal is transcoded by the transcoder and provided to a second repeater using a second audio encoding format. The second repeater then broadcasts the voice call to any communication unit within range using the second audio encoding format.

Abstract: The present disclosure provides an efficient and effective method for allocating provisional PUIDs and PGIDs to subscriber units and groups during a failure, such that when the communication system recovers, there is a decrease in or elimination of the number of dropped or missed communications. The present disclosure reserves a range of provisional PUIDs and PGIDs for resource controllers operating in a region of system failure to assign when subscriber units roam into the region of failure in the communication system. The present disclosure addresses creating PUID and PGID ranges for resource controllers to assign to roaming subscriber units in order to allow for assignment of PUIDs and PGIDs during periods of subsystem isolation and site trunking, i.e., when the particular site or subsystem cannot communicate with the rest of the communication system. The present disclosure also addresses recovering from these situations, re-registration, and reallocation of PUIDs and PGIDs.

Abstract: A transmitting unit combines a slot identifier (SI) and a block identifier (BI) in each header that is transmitted with the data to allow a receiving unit to associate previously received data blocks with retransmissions, or retries, of the same respective data blocks in order to perform bit error detection in accordance with a hybrid or selective ARQ protocol. The receiving unit uses the SI and BI contained in the MHBKs to determine a correspondence between a retried data and a previously transmitted data block.

Abstract: Methods, systems, and apparatuses for antenna designs for radio frequency identification (RFID) tags are described.

Abstract: A system and method for processing calls in a communication system utilizing distributed signaling. When a call signal having distributed identification data is received on a communication channel, the call information (such a voice, data, video, etc.) is initially passed through the system without verification until sufficient identification data (such as the color code) has been obtained to determine whether the source of the call is valid. Once sufficient identification data has been obtained, the source is verified. If the source is valid, the call information continues to be passed through the system. However, if source is invalid, the call information is blocked for the present call as well as for subsequent calls on the same communication channel, and passing of the call information through the system does not resume until a received call is subsequently assessed to be valid.

Abstract: A method and apparatus are provided for reducing truncation of time sensitive information such as audio in a trunked radio system having a plurality of zone controllers. The method includes the steps of receiving a call request from a calling radio or wireline console by a controlling zone controller of the plurality of zone controllers and measuring a time necessary to set up a call connection between the controlling zone controller and a plurality of called radios or wireline consoles where the call connections of the plurality of called radios or wireline consoles are each set up through a different participating zone controller of the plurality of zone controllers. The method also includes the steps of determining a largest relative measured time among the measured times and buffering audio information from the calling radio for a time period proportional to the determined largest relative time.

Abstract: Methods, systems, and apparatuses for a reader transceiver circuit are described. The reader transceiver circuit incorporates a frequency generator, such as a surface acoustic wave (SAW) oscillator. A reader incorporating the reader transceiver circuit is configured to read a tag at very close range, including while being in contact with the tag. The transceiver can be coupled to various host devices in a variety of ways, including being located in a RFID reader (e.g., mobile or fixed position), a computing device, a barcode reader, etc. The transceiver can be located in an RFID module that is attachable to a host device, can be configured in the host device, or can be configured to communicate with the host device over a distance. The RFID module may include one or more antennas, such as a first antenna configured to receive a magnetic field component of an electromagnetic wave and a second antenna configured to receive an electric field component of an electromagnetic wave.

Abstract: A method and system are provided for enhanced signal detection in a frequency selective fading channel. Improved signal detection is realized by replacing single matched filters with multiple matched filters. The single matched filter spectrum is partitioned by frequency into M matched filter groups, where M is a positive integer greater than one. The filter bandwidth of each of the M matched filters is less than the bandwidth of the single matched filter from which they are derived. The M matched filters are provided to filter in parallel fashion the input signal into M sub-spectrums of the signal. The input signal is filtered through the M matched filters and also sent to the energy detector. The matched filter outputs are combined and the received signal is detected using the combined output and the energy in the received signal.

Abstract: A method and circuit are described for estimating I and Q amplitude imbalance occurring in a signal received by a direct conversion receiver (DCR). The DCR generates a mixing signal having a frequency substantially the same as the carrier signal of the signal received by an antenna. A mixing module mixes the mixing signal at different phases with the received signal to generate I and Q baseband signals. A frequency offset circuit generates an offset signal having a frequency offset from the carrier signal frequency. A coupling circuit selectively decouples the antenna from the DCR and couples the offset signal to the mixing module to generate a baseband test signal in the I and Q signal paths for determining an imbalance in the amplitudes of the baseband test signals between the I and Q signal paths.

Abstract: A system and method for dynamically altering detection criterion value at a receiving device based on the portion of a call signal being received. A receiving device is configured to extract a first call signal portion from the call signal, and compare the first call signal portion to a plurality of call information portions, wherein each call information portion has a detection criterion value. If the first call signal portion matches one of the call information portions, the receiving device adjusts the detection criterion value for at least one of the plurality of call information portions, extracts a second call signal portion from the call signal, and compares the second call signal portion to the plurality of call information portions.

Abstract: An echo canceling circuit comprising a double talk detector, an upper band signal filter configured to pass only near-end upper band signals to the double talk detector and remove lower band signals, an adaptive filter circuit, a control circuit operatively coupled to the double talk detector and to the adaptive filter circuit, and a threshold estimator configured to iteratively calculate an upper adaptive decision threshold value and a lower adaptive decision threshold value. The double talk detector declares near-end speech to be present if an estimated power level of the upper band signals exceeds the upper adaptive decision threshold value, and declares the near-end speech to be absent if the estimated power level of the upper band signals falls below the lower adaptive decision threshold value for a predetermined number of iterative cycles.

Abstract: A mobile communication system is described. The system has an infrastructure that includes base stations and has mobile stations, a mobile terminal and a mobile controller. Each mobile station is operable to communicate with one of the base stations. The mobile terminal is coupled to first and second mobile stations to provide a communication link to at least one of the base stations. The mobile controller sends instruction messages to the mobile stations regarding connectivity with the base stations. The mobile terminal, the mobile controller and the first and second mobile stations are carried on a moving object. The mobile controller makes decisions and issues instructions to the mobile stations relating to the base station by which they should each be served with to maintain a communication link between the mobile terminal and a serving base station via at least one of the mobile stations.

Abstract: A method of operation in a mobile communication system includes a mobile station, a first network capable of serving the mobile station as a home network and a second network capable of serving the mobile station as a visited network, including carrying out in the home network the steps of: generating a random seed (RS), modifying the random seed by combination with an authentication key (K) held by the home network and the mobile station to form session keys (KS and KS?), sending the session keys (K?S and K?S?) to the visited network to permit authentication of the mobile station, and characterized in that the following steps are carried out in the home network: providing a further modification key (SMK), and carrying out a further key modification (of KS and KS?) in the production of the session key (K?S and K?S?) using the further modification key (SMK).