Abstract: A multi-band RF transmitter circuit (30) for a wireless communication device combines a plurality of RF transmission blocks into a single transceiver integrated circuit which includes a shared broadband SVGA (32), a shared tunable balun (34), and an output switching network (38) at the output of the balun to support three different frequency bands. The outputs of the multi-band RF transmitter circuit are connected to separate external power amplifier circuits (42-44), where each power amplifier circuit generates an amplified signal for one of the plurality of predetermined frequency bands.

Abstract: A multi-band RF transmitter circuit (30) for a wireless communication device combines a plurality of RF transmission blocks into a single transceiver integrated circuit which includes a shared broadband SVGA (32), a shared tunable balun (34), and an output switching network (38) at the output of the balun to support three different frequency bands. The outputs of the multi-band RF transmitter circuit are connected to separate external power amplifier circuits (42-44), where each power amplifier circuit generates an amplified signal for one of the plurality of predetermined frequency bands.

Abstract: A stacked double balanced mixer (220) includes a double balanced mixer (320) and a first cross coupled differential mixer (330). The double balanced mixer (320) includes two input transistors (321, 322) and four cross coupled output transistors (323-326). The first cross coupled differential mixer (330) includes four cross coupled input/output transistors (331-334) and a second mixer output (227, 228). The four cross coupled input/output transistors (331-334) have first output terminal pairs DC coupled in series to second output terminal pairs of the four cross coupled output transistors (323-326). The stacked double balanced mixer (220) generates, at the second mixer output (227,228), a second IF differential output signal having a second IF frequency at a difference of a radio frequency of a differential input signal and the sum of first and second LO frequencies, respectively, of first and second LO signals.

Abstract: A pager receiver includes at least one lock-out circuit, an out-of range circuit, and a single timer coupled to the lock-out and out-of range circuits and responsive to timing signals generated by the pager for generating an initiated one of either the lock-out timer interval or out-of range time interval. Each lock-out circuit of the pager receiver corresponds to an address function programmed therein and is activated by the function detect signal generated in response to the initial decoding of the corresponding address function to initiate the generation of the lock-out time interval by the single timer and to inhibit the corresponding alert annunciation from responding to subsequently generated function detect signals corresponding thereto for the duration of the lock-out time interval. The single timer is also initiated to generate the out-of-range time interval at the generation of each sync pulse timing signal by the pager receiver, but only in the absence of an activated lock-out circuit.

Abstract: A heterodyne stage of a receiver which includes a conventional mixer circuit and local oscillator circuit further includes a differential amplifier circuit which measures the amplitude of the injection signal generated by the local oscillator circuit and controls it precisely to a desired reference level by adjusting the current bias supply to the local oscillator circuit within a banded range to ensure start-up of the local oscillator upon energization and to protect against loss of injection signal under all operating conditions. The differential amplifier circuit provides for a precise amplitude reference setting and sufficient closed-loop gain for controlling the amplitude of the injection signal with a minimum of error between the measured and reference values.

Abstract: A constant propagation delay current reference is provided having an external source providing a reference frequency signal. A phase lock loop is provided which is responsive to the reference frequency signal and to an operating frequency signal to provide a current reference signal at the output of the loop. The current reference signal is provided to a current to frequency converter which generates the operating frequency signal. A current mirror, also coupled to the phase lock loop output provides an output current proportional to the current reference signal which is suitable for providing the injector current for I.sup.2 L devices. The output current tracks the process, voltage and temperature variations of the integrated circuit, allowing the injector currents to be optimized for maintaining constant propagation delay in the circuits being powered.

Abstract: Apparatus and method is disclosed for automatically, or by selective response, call forwarding a message to one or more system pagers which have an acknowledge back capability.In one embodiment, disclosed apparatus automatically forwards a message to another system pager upon the initially called pager failing to acknowledge back within a predetermined time period. Such other pager is determined from a set paging hierarchy included within the paging terminal apparatus itself.In another embodiment, wherein the system pagers have multiple acknowledge back response capability, a called pager can request the received message be additionally call forwarded to one or more other system pagers in accordance with the particular acknowledge back response chosen by the called pager user.

Abstract: A paging system is provided having page transmission means responsive to a message origination device for transmitting selective call paging signals and messages. A query signal is also transmitted a predetermined minimum time period from the corresponding paging signal. A plurality of transceivers are provided responsive to the selective call paging signals and messages, and further responsive to the query signals for enabling the generating and transmitting of a response signal. Receivers are provided for receiving the transmitted response signals. The received response signals are then delivered to the message origination device from which the original message originated.