Abstract: A variable phase shift network (420) for a phase quadrature signal generator (320, 370) includes a variable current controller (909), a first NPN transistor (801) and a second NPN transistor (802). The variable phase shift network (420) produces a first quadrature input signal (830), a second quadrature input signal (834), a first quadrature output signal (821) and a second quadrature output signal (826) responsive to receiving a first differential input signal (919) and a second differential input signal (925).

Abstract: Prior to placing a call, a receiver (24) in a radio (10) receives a phone number transmitted by a calling party to produce a received phone number (38). The received phone number (38) is stored in a memory unit (16) of the radio (10). Numeric digits forming a prefix number (40) are inserted before the received phone number (38) in the memory unit (16) responsive to a number of digits in the received phone number (38) to produce an edited phone number (39). A transmitter (20) in the radio (10) transmits the edited phone number (39) to place the call to the received phone number (38). This method for editing a received phone number (38) prior to placing a call to the received phone number (38) advantageously simplifies the dialing process when placing the call to the received phone number (38).

Abstract: A wireless communication device (101), such as a radiotelephone or a pager, comprises a signal generator (200), a radiator (202), a sensor (204) and a controller (206) to form an electromagnetic wave proximity sensor (201). The signal generator (200) generates a signal (210). The radiator (202) radiates the signal (210) to produce an electromagnetic field (212) near the radiator (202). The electromagnetic field (212) changes by a predetermined amount responsive to the proximity (214) of the radiator (202) to a predetermined object (216), such as a human body (232), external to the wireless communication device (101). The sensor (204) provides an indication (218) of the predetermined amount of change in the electromagnetic field (212). The controller (206) controls circuitry (208), such as a tactile alert device (416) and an audible alert device (418), in the wireless communication device (101) responsive to the indication (218) of the predetermined amount of change in the electromagnetic field (212).

Abstract: A dual mode cellular radiotelephone subscriber unit (802) comprises a diversity receiver (812) and a controller (814). The diversity receiver (812) receives either a first radio frequency (RF) signal (808) modulated by a digital modulation method (805) or a second RF signal (810) modulated by an analog modulation method (807). In one embodiment, the controller (814) controls the diversity receiver (812) responsive to a first diversity algorithm (834) when the diversity receiver (812) receives the first RF signal (808) modulated by the digital modulation method (805), and responsive to a second diversity algorithm (836) when the diversity receiver (812) receives the second RF signal (810) modulated by the analog modulation method (836).

Abstract: A portable radiotelephone (101) cooperatively operates with a cordless base station (115) over the local coverage area using cellular frequency channels. Both the portable radiotelephone (101) and the cordless base station (115) scan the available channels to generate separate priority lists. The portable radiotelephone (101) and the cordless base station (115) categorize the available channels in its own priority list from best to worst. The priority list from both the portable radiotelephone (101) and the cordless base station (115) are combined to form a master priority list. The cordless telephone system then assigns the clearest available channel from the master priority list for use in the cordless telephone system. Thus, interference to and from the cellular system and other users of the cellular frequencies is minimized and the need for frequency planning is eliminated.

Abstract: A portable electronic device (10) comprises a radio circuit (150) contained in a housing (152) having positive (156) and negative (158) contacts electrically coupled to the radio circuit (150). A substantially flat, elongated, flexible battery cell, forming a compliant energy storage device (32), provides a single, continuous wrist band (30) and has positive (160) and negative (162) terminals. A latch mechanism (176) releasably secures the housing (152) to the wrist band (30) between opposite ends (172, 174) of the wrist band (30), and permits the contacts (156, 158) of the housing (152) to align with and abut the respective terminals (160, 162) of the wrist band (30) while the wrist band (30) is worn on the user's wrist. Multiple housings (152, 180) may be stacked to add electrical functions.

Abstract: An apparatus and method provides identification of a failed subscriber unit (102) in a wireless communication system (100). In a first embodiment, the subscriber unit (102) performs a self test to detect a failure (302) of at least a portion of the subscriber unit (102). If a failure is detected, a message, stored (203) in the subscriber unit (102) is produced. In a second embodiment, the wireless communication system (100) includes a subscriber unit (102) including a receiver (102) communicating with a transmitter (101). The subscriber unit (102) has a unique code selectable by the transmitter (101). The subscriber unit (102) performs a self test to detect a failure (402) of at least a portion of the subscriber unit (102). If a failure is detected, a generic code is substituted (404) for the unique code. The transmitter (101) pages (406) the subscriber unit (102) with its generic code and transmits (407) an indication of the detected failure to the paged subscriber unit (102).

Abstract: A wrist-carried radiotelephone (10) comprises a housing (12), radiotelephone circuitry (90) and a bracelet (16). The radiotelephone circuitry (90) is disposed in the housing (12). The bracelet (16) is connected to the housing (12) and secures the housing (12) to a user's wrist. The bracelet (16) further comprises a plurality of links (18, 20, 22, 24). Each link (18, 20, 22, 24) of the plurality of links (18, 20, 22, 24) has a battery (26, 28, 30, 32) disposed therein. Adjacent links (18, 20, 22, 24) of the plurality of links (18, 20, 22, 24) are mechanically coupled together using a hinge (72, 74). Adjacent batteries (26, 28, 30, 32), disposed in respective adjacent links (18, 20, 22, 24) of the plurality of links (18, 20, 22, 24), are electrically coupled together using electrical conductors (50, 52, 58, 60). The batteries (26, 28, 30, 32) disposed in the links (18, 20, 22, 24) provide power to the radiotelephone circuitry (90).

Abstract: A gain controller (130) for a radio frequency (RF) transmitter (102) controls a power level of a signal (123) transmitted within a predetermined range of output power levels. The gain controller (130) provides the first gain control signal (131) and the second gain control signal (133) responsive to an output power level control signal (150). The first gain control signal (131) controls a gain of a first variable gain stage (144) to vary the power level of the transmit signal (115) at an intermediate frequency causing the output power level of the transmit signal (123) to vary over a lower range of the predetermined range of output power levels. The second gain control signal (133) controls a gain of the second variable gain stage (120) to vary the power level of the transmit signal (121) at a radio frequency causing the output power level of the transmit signal (123) to vary over an upper range of the predetermined range of output power levels.

Abstract: An error suppressing circuit (301) and method therefor for a phase locked loop (PLL) (300). According to one embodiment of the present invention, a transient condition, for example, a bandwidth switch, in the PLL (300) is detected. The PLL (300) is opened for a period of time (509) responsive to detecting the transient condition. The phase of a reference frequency signal (115) and the phase of a output frequency signal (116 or 117) are synchronized after a lapse of the period of time (509). The PLL (300) is closed responsive to the phase of the reference frequency signal (115) and the phase of the output frequency signal (116 or 117) being synchronized. The present envention advantageously reduces the length of time it takes for the PLL (300) to correct for the phase and frequency error generated by the transient condition, and is capable of operating with various types of PLLs.

Abstract: A multiplexed synchronous/asynchronous data bus uses three communications lines (T, C, R) to convey bi-directional synchronous data between two data devices at a relatively low data transfer rate. The data bus is configured as a full-duplex asynchronous data bus by communicating a false address between the two data devices on two communications lines (T, C) using the synchronous data bus, holding the two communications lines (T, C) in a logic high state for a period of time, and continuing to hold one of the two communications lines (C) in the logic high state during full-duplex asynchronous communication. Full-duplex asynchronous data can then communicated between the two data devices at a higher data transfer rate on two of the three communications lines (T, R).

Abstract: A portable radio transceiver (100) includes a transmitter (101) and a receiver (103) operating at different respective frequencies. The transmitter (101) is capable of producing an undesired signal (121) including a frequency substantially equal to the receiver operating frequency (107). A first antenna (102) is coupled to the transmitter (101). A second antenna (104) is coupled to the receiver (103) and electrically isolated (122) from the first antenna (102) by a predetermined degree such that the undesired signal (121) received by the second antenna (104) is attenuated by the predetermined degree of electrical isolation (122). An optional filter (112), coupled to an input terminal of an amplifier (113) in the transmitter (101), is adapted to attenuate the undesired signal (121) such that the undesired signal (121) received by the second antenna (104) is further attenuated.

Abstract: A portable radiotelephone (200) adjusts its transmit power responsive to the position of a movable antenna (213). The antenna (213) is movable between a retracted (313) and an extended position (314). The portable radiotelephone (200) transmits at low power when the antenna (213) is retracted and at high power when the antenna (213) is extended. Additionally, the portable radiotelephone (200) can notify a remote base station of the change in transmit power at any time during transmission.

Abstract: A disposable portable radiotelephone subscriber unit (101) comprises a power supply (255), a transceiver (205, 207) and a controller (215). The power supply (255) has stored therein a predetermined measure of power capacity (281). The transceiver (205, 207) is permitted to operate for a predetermined period of time (405) responsive to the predetermined measure of the power capacity (281). The controller (215) monitors a rate of depletion of the predetermined measure of the power capacity (281). The controller (215) permits operation of the transceiver (205, 207) when the power capacity (281) is being depleted at a desirable rate, thereby decreasing the predetermined period of time (405) that the transceiver (205, 207) is permitted to operate. The controller (215) prevents operation of the transceiver (205, 207) when the power capacity (281) is being depleted at an undesirable rate, thereby prolonging the predetermined period of time (405) that the transceiver (205, 207) is permitted to operate.

Abstract: A method (250) determines weighting coefficients (188, 190, 192) in a code division multiple access (CDMA) radio receiver (100). A representation (172) of a desired RF signal (166) is received (108, 124, 127). A plurality of data signals (176, 180, 184) are generated responsive to the representation (172) of a desired RF signal (166). A plurality of pilot signals (178, 182, 186) are generated responsive to the first representation (172) of a desired RF signal (166). A total received signal power (174) is measured (128). A plurality of weighting coefficients (188, 190, 192) are determined responsive to the plurality of data signals (176, 180, 184), the plurality of pilot signals (178, 182, 186) and the total received signal power (174).

Abstract: A method (300) for adaptively adjusting weighting coefficients (188, 190, 192) in a code division multiple access (CDMA) radio receiver (100). A representation (172) of a desired RF signal (166) is received (108, 124, 127). A plurality of pilot signals (178, 182, 186) are generated responsive to the representation (172) of a desired RF signal (166). Each of a plurality of weighting coefficients (188, 190, 192) is determined responsive to more than one of the plurality of pilot signals (178, 182, 186).

Abstract: A radiotelephone subscriber unit (101) comprises a memory unit (259) having stored therein an identification sequence including a phone number (MIN1 and MIN2) and an electronic serial number (ESN). The phone number (MIN1 and MIN2) is common to at least one other portable radiotelephone subscriber unit in a radiotelephone system (102) The electronic serial number (ESN) is unique to the portable radiotelephone subscriber unit (101) in the radiotelephone system.