Abstract: An indication is received to relocate leakage in a transmission signal to be transmitted. A frequency change associated with relocating the leakage in the transmission signal is obtained. The leakage in the transmission signal is relocated based at least in part on the frequency change.

Abstract: A method of transmitting information comprises grouping a plurality of active time slots into a plurality of sub-frames wherein each of the sub-frames includes a plurality of contiguous active time slots, transmitting data during a first one of the plurality of sub-frames, waiting during an inactive period and transmitting data during a second one of the plurality of sub-frames. A system configured to transmit information, comprises a controller configured to group a plurality of active time slots into a plurality of sub-frames wherein each of the sub-frames includes a plurality of contiguous active time slots, and a transmitter coupled to the controller, configured to transmit data during a first one of the plurality of sub-frames, wait during an inactive period and transmit data during a second one of the plurality of sub-frames.

Abstract: A dual-mode frequency and phase RF modulator (11) for use in a transmitter of a radiotelephone. A dual-mode modulation approach is employed wherein, in the analog (FM) mode of operation, a phase modulator, such as a .pi./4-shift DQPSK modulator, is bypassed and may be powered down. A frequency modulated RF carrier is coupled through a bypass circuit (52) to a modulator output node (50) for transmission from the radiotelephone. In the digital mode of operation, the bypass signal path is disabled, the .pi./4-shift DQPSK modulator is enabled, and in-phase (I) and quadrature (Q) signals are input to the .pi./4-shift DQPSK modulator which provides a phase modulated RF carrier that is coupled to the modulator output node for transmission from the radiotelephone. The teaching of this invention can be employed with radiotelephones having, by example, TDMA/analog capability or CDMA/analog capability.

Abstract: This invention teaches a method, and circuits that operate in accordance with the method, for adaptively controlling the transmitted power of a CDMA transmitter (50, 102). The method includes the steps of: (a) presetting a register, such as a counter (112), with an estimate of a maximum transmitter gain signal, the counter having an count output that is a representation of a maximum transmitter gain signal (TX max); (b) deriving a transmitter gain signal (TX gain) from a received CDMA signal; (c) comparing TX max to TX gain and, if TX gain is greater than TX max, (d) applying a gain control signal to the transmitter that is derived from TX max, and (e) enabling the counter to increase its count; else, if TX gain is less than TX max, (f) applying a gain control signal to the transmitter that is derived from TX gain, and (g) disabling the counter from increasing its count.

Abstract: The circuit amplifies an input RF band of signals and exhibits a signal gain in decibels that is a linear function of a logarithmic control signal input. The circuit employs a transistor having an emitter electrode connected through an inductor/resistor combination to a source of common potential. Within a limited band of RF frequencies, the resistor inductor combination appears to be a high impedance. A PIN diode is connected in shunt across the resistor/inductor combination and, in response to a control current, alters its RF resistance. A capacitor is connected across the emitter of the transistor and provides a tuning function so that, at the mid-frequency of the RF band, a resonant tuned circuit results, thereby causing a high value resistive load to appear across the PIN diode. In this manner, linear gain control is achieved by varying a DC control current through the PIN diode.

Abstract: A circuit amplifies an input RF band of signals and exhibits a signal gain in decibels that is a linear function of the logarithm of a control signal input. The circuit comprises a first amplifier stage having an output node that exhibits a first RF complex admittance within the RF band of signals. A second amplifier stage has an input node coupled to the output node of the first amplifier stage and exhibits a second RF complex admittance within the RF band of signals. A PIN diode, used as a gain control element, is shunt connected between the control signal input and the output node. An RF reactance circuit is also shunt connected between the output node and a common potential. The RF reactance circuit has a third admittance that is chosen to negate the imaginary portions of the first and second complex admittances, whereby the total admittance is substantially real and enables the PIN diode to see a minimal resistive load.

Abstract: A phaseshift network (2) exhibits approximately equal impedances to the outputs of an IQ mixer (10), over a range of modulation frequencies (Fm). The phaseshift network furthermore exhibits an approximately equal time delay for the I and Q modulated signals propagating therethrough. The phaseshift network includes a first branch having an input node for receiving a first frequency signal that varies within a range of frequencies about a frequency Fo. The first branch includes a phaseshifter for providing a frequency signal representative of the first input signal that is retarded by a first predetermined number of degrees. The phaseshift network further includes a second branch having an input node for receiving a second frequency signal that varies within a range of frequencies about the frequency Fo. The second branch includes a phaseshifter for providing a frequency signal representative of the second input signal that is advanced by a second predetermined number of degrees.