Abstract: A receiver (100) that includes an antenna (101) employs a method and apparatus for producing diversity gain of a signal (106) received by the antenna (101), wherein the signal (106) is subject to a time-variant fading condition. Upon receiving the signal (106), the receiver (100) determines a signal quality metric of the signal (106) and compares the signal quality metric to a quality threshold. When the signal quality metric is below the quality threshold, the receiver (100) orients a predetermined antenna pattern (304) of the antenna (101) to improve the signal quality metric, thereby producing the diversity gain.

Abstract: A transmitter that includes an amplifying element, an antenna, a gain stage, and a closed loop feedback may compensate for varying antenna loads without an isolator. This may be accomplished by determining the effects of the varying loading on overall loop gain. Knowing the effects, the transmitter adjusts the gain of the gain stage to maintain a constant overall loop gain, thus eliminating the need for an isolator.

Abstract: Communications may be established based on geographic location when a communication resource controller (101) transmits a communication message (119), which includes a message ID (120) a communication payload (121), and a set of geographic coordinates to a plurality of communication units (102, 103). Each of communication units (102, 103) upon receiving the communication message (119), compares its identification code (123) with the message ID (120). If a match occurs, the communication unit (102, 103) then determines its geographic location. Having obtained the geographic location, the unit determines whether its present location is within the area defined by the set of geographic coordinates and, if so, adjust its receiver to receive the communication payload (121).

Abstract: Resource controllers (14) within a multisite communication system (20) selectively and automatically assume primary (45) and secondary (53) control modes of operation in order to ensure that adequate communication resources are assigned throughout the system at necessary sites in order to include talk group members that are dispersed throughout the system.

Abstract: In a communication system utilizing DMT technology to couple a primary site (102) to a plurality of secondary sites (104-108), infrastructure control channels are established in the following manner. Having obtained a plurality of site bit loading tables, the primary site (102) generates a control channel bit loading table from the plurality of site bit loading tables. From the control channel bit loading table, the primary site selects at least one carrier channel to function as the control channel. The selection is based on bandwidth requirements for the control channel.

Abstract: A packet data communication system (100) that includes a packet data routing network (101, 103) and a plurality of base sites (105-107) employs a method (400, 500) and apparatus for providing packet data to a communication unit (109). The packet data routing network (101, 103) provides a packet (201-208) of data to at least two of the base sites (105-107), one of the base sites (e.g., 105) being the site currently serving the communication unit (109) and the other base site or sites (e.g., 106, 107) being possible handoff targets. The serving base site (105) transmits at least a first portion (e.g., 201-203) of the packet (201-208) to the communication unit (109) and the communication unit (109) receives the transmitted packet or portion thereof. However, if during transmission of the packet (201-208) the communication unit (109) requires a handoff to one (e.g.

Abstract: A controlled collapse chip connection device can be heat sinked in the following manner. A carbon composition heat sink (102) having a thermal expansion coefficient substantially equal to a thermal expansion coefficient of the controlled collapse connection chip device (101) is positioned in a proximate location to a fabricated thermal mating area (104) of the controlled collapse chip connection device (101). The carbon composition heat sink (102) is then thermally bonded to the thermal mating area (104) of the controlled collapse connection chip device (101).

Abstract: Time slots may be allocated within a communication system when a communication unit transmits a first packet to a time slot allocator. Upon receiving the first packet, the time slot allocator determines whether the first packet contains a request for allocation of n-time slots or a request to transmit multiple packets. When the first packet contains the request for allocation of n-time slots, the time slot allocator allocates the n-time slots to the communication unit when the n-time slots are available, wherein the n-time slots are allocated contiguous in time. When the first packet contains the request to transmit multiple packets, the time slot allocator allocates time slots to the communication unit until the multiple packets have been transmitted, wherein the time slots are allocated contiguous in time.

Abstract: A filter (200) having an input terminal (208), an output terminal (209), and a common terminal (210) includes two impedance inverters (201,202) and a first resonator (203) that is operable at a resonant frequency. Each impedance inverter (201, 202) is coupled to the common terminal (210) at a common node (223) and includes a corresponding input node (221,225) and output node (222, 226). The input node (221) of the first impedance inverter (201) is coupled to the input terminal (208). The input node (225) of the second impedance inverter (202) is coupled to the output node (222) of the first impedance inverter (201), while the output node (226) of the second impedance inverter (202) is coupled (e.g., via a second resonator (205)) to the output terminal (209). The first resonator (203) is coupled between the input terminal (208) and the output terminal (209).

Abstract: A communication system utilizes rotated bursts of voice channels to implement mobile assisted handoff (MAHO). Mobile stations measure the voice channels of adjacent cells as hopping frequencies are rotated from frame-to-frame of the communication system. Measurement of the voice channels of adjacent cells can be performed by mobile stations during timeslots subsequent to their receive and transmission so that measurement during a timeslot dedicated to a control channel related to the adjacent cells is not necessary.

Abstract: In a wide area communication system that includes a central controller, a plurality of sites, and a plurality of subscriber units, a requesting subscriber unit can locate a neighboring subscriber unit in the following manner. Each of the plurality of subscriber units registers with the central controller. The central controller stores registration information in a database. When the requesting subscriber unit transmits a request for a subscriber identification of a neighboring subscriber unit, the central controller determines whether the neighboring subscriber unit exists. When the neighboring subscriber unit exists, the central controller transmits the subscriber identification of the neighboring subscriber unit to the requesting subscriber unit.

Abstract: A feed forward amplifier network (100) employs a method (300) and apparatus for reducing distortion contained in an output signal (142) of an amplifier circuit (101). A modulator (118, 120) modulates (303) an input signal (141) of the amplifier circuit (101) with a reference modulation. The amplifier circuit (101) amplifies (305) the modulated signal, introducing nonlinear distortion in the process. A modulation determination circuit (107, 109, 115) determines (307) the reference modulation in the amplified signal and provides the determined modulation to an adjustment circuit (105). The adjustment circuit (131,133, 135) adjusts (309) a characteristic of the determined modulation in response to a control signal (153,155) and combines (137, 311) the adjusted modulation with the amplified signal (142) at the output of the amplifier circuit (101) to produce a corrected signal (151).

Abstract: A diversity receiver that receives modulated signals may determine signal usability of the received signals in the following manner. A modulated signal that includes a desired component and an undesired component is received in each receiver branch of the diversity receiver, wherein the desired component includes an originally transmitted signal and the undesired component includes noise and interference. Each receiver branch estimates the desired and undesired components and processes the modulated signal with a channel gain/phase estimator, a complex conjugator, and a complex mixer to produce a complex output. The complex output of each receiver branch is derived independently of the undesired component and combined to produce a diversity resultant. The diversity receiver estimates the signal usability of the diversity resultant based on the estimated desired components and the estimated undesired components.

Abstract: A method for establishing a logical connection between a plurality of sites (101-110) and either a plurality of site controllers (112-115) or a switching center (117) in a radio communication system (100) may be accomplished in the following manner. A first site (101) is selected from a first pair of sites (101,104), wherein the geographical separation (119) between the first pair of sites (101, 104) exceeds the geographical separation between any other pair of sites. Upon selecting the first site (101 ), at least a second site (106, 108) is selected to form a group of selected sites (101,106-108). The group of selected sites (101,106-108) is assigned to a first site controller (112), or a first control portion (201) of the switching center (117), such that communication resources provided by the group of selected sites (101,106-108) can be accommodated by the assigned controller (112), or control portion (201).

Abstract: Location of an unauthorized communication unit 102 may be detected in a wireless communication system 100 by determining that an identification code being used by the communication unit has been validated in an unauthorized manner. Having determined this, the site from which the communication unit is transmitting is determined. With the transmitting site determined, RF receivers 110, 111 in the proximity of the transmitting site are enabled to receive a subsequent RF transmission from the communication unit. The RF transmissions received by the RF receivers are then used to calculate the location of the communication unit.

Abstract: In a communication system, a communication unit may conserve source energy when it is inactive in the following manner. The control channel is partitioned into a predetermined number of windows and a system window which are transmitted on the control channel in a round robin manner. When the communication unit registers with the communication system, it is assigned to a window group. The communication unit then monitors only the system window to determine whether the window group that its been assigned to is also assigned to one of the predetermined number of windows. When the window that has been assigned to the window group is being transmitted on the control channel, the communication unit activates to monitor that window. Once the window is no longer being transmitted, the communication unit deactivates until the system window is being transmitted or the window assigned to the window group is being transmitted.

Abstract: A dispatch radio communication system (100) employs a method (200) and apparatus (101) for assigning one of a console station's control modules (113-115) to a communication resource. The assignment is initiated by associating (203) each control module (113-115) with a group of supported resource features and associating (205) each communication resource with a group of employed resource features. The latter association is then used to establish (211 ) a minimum set and an extended set of resource feature requirements for a particular communication resource that is to be added to a console station (109). The former association is used to identify (217) a group of candidate control modules (113-115) at the console station (109) that can support at least the minimum set of resource feature requirements. Upon identification of the candidate group (113-115), the candidate control module (e.g.

Abstract: In a multiple site communication system, a method for determining when to hand off a communication that is occurring on one communication resource to another communication resource may be accomplished in the following manner. Once a communication unit is allocated a communication resource, it begins to monitor signal usabilities of the allocated communication resource and a predetermined set of alternate communication resources. A broadcast unit associated with the allocated communication resource also monitors the signal usability of the allocated communication resource. When the signal usability of the allocated communication resource is determined to be unfavorable by the communication unit or the broadcast unit, one of the alternate communication resources is selected based on calculated signal usability, such that the communication unit can continue the communication.

Abstract: A database unit monitors the communications occurring within at least one communication system for a change status indicator of communication or broadcast units. Upon receiving the change status indicator, the database unit compares the one received with a stored change status indicator for the unit. When the stored change status indicator does not match the one received, the database unit indicates that the unit has undergone an unauthorized modification.