Patent classifications
H03C3/0933
Frequency modulation system based on phase-locked loop capable of performing fast modulation independent of bandwidth and method of the same
The present invention relates to a frequency modulation method based on a phase-locked loop capable of performing fast modulation independent of bandwidth. A frequency modulation system based on a phase-locked loop capable of performing fast modulation independent of bandwidth according to the present invention includes a loop filter including a proportional path and an integral path to determine a bandwidth of a phase-locked loop, a voltage-controlled oscillator configured to adjust a frequency according to an output of the loop filter, and a slope alternator configured to alternate an input current of the loop filter, wherein the slope alternator is located in the integral path of the loop filter to generate an offset current at a moment of change from a modulation rise to a modulation fall.
1-16 & 1.5-7.5 Frequency Divider For Clock Synthesizer In Digital Systems
A frequency divider unit has a digital frequency divider configured to divide by an odd integer, and a dual-edge-triggered one-shot coupled to double frequency of an output of the digital frequency divider. The frequency divider unit is configurable to divide an input frequency by a configurable ratio selectable from at least non-integer ratios of 1.5, 2.5, and 3.5. In embodiments, the frequency divider unit relies on circuit delays to determine an output pulsewidth, and in other embodiments the output pulsewidth is determined from a clock signal. In embodiments, the unit is configurable to divide an input frequency by a configurable ratio selectable from at least non-integer ratios of 1.5, 2.5, 3.5, 4.5, 5.5, 6.5, and 7.5 as well as many integer ratios including 2, 4, 6, and 8. In embodiments, the digital frequency divider is configurable to provide a 50% duty cycle to the one-shot.
Performance indicator for phase locked loops
Performance indicator circuitry is provided for characterizing performance of a phase locked loop (PLL) in a phase path of a polar modulator or polar transmitter that is used to generate a phase modulated RF signal. The PLL includes an oscillator, a high pass path, and a low pass path. The low pass path includes a loop filter. The performance indicator circuitry includes first input circuitry and parameter calculation circuitry. The first input circuitry is configured to input a loop filter signal from the loop filter. The parameter calculation circuitry is configured to compute a value for a performance indicator based on the loop filter signal and control or characterize an aspect of operation of the PLL based on the value.
TYPE-I PLLS FOR PHASE-CONTROLLED APPLICATIONS
A type I phase locked loop (PLL) includes an oscillator and a feedback path to a phase detector. A first frequency and first relative phase of a first output signal are locked to a frequency and a phase of a first input signal. A second frequency and second relative phase of a second output signal are locked to a frequency and a phase of a second input signal. A correction to the PLL is applied to perform one of: adjusting the second relative phase to equal the first relative phase and adjusting the oscillator frequency.
FREQUENCY MODULATION SYSTEM BASED ON PHASE-LOCKED LOOP CAPABLE OF PERFORMING FAST MODULATION INDEPENDENT OF BANDWIDTH AND METHOD OF THE SAME
The present invention relates to a frequency modulation method based on a phase-locked loop capable of performing fast modulation independent of bandwidth.
A frequency modulation system based on a phase-locked loop capable of performing fast modulation independent of bandwidth according to the present invention includes a loop filter including a proportional path and an integral path to determine a bandwidth of a phase-locked loop, a voltage-controlled oscillator configured to adjust a frequency according to an output of the loop filter, and a slope alternator configured to alternate an input current of the loop filter, wherein the slope alternator is located in the integral path of the loop filter to generate an offset current at a moment of change from a modulation rise to a modulation fall.
ACCELERATED CHANNEL SCANNING WITH A TWO-POINT-MODULATED PHASE-LOCKED LOOP
A receiver is provided having a two-point-modulated phase-locked loop for the rapid scanning of the signal strength of a plurality of frequency channels. The two-point modulation includes a modulation of a frequency gain by an oscillator in the phase-locked loop and a modulation of a frequency division by a divider in the phase-locked loop.
Accelerated channel scanning with a two-point-modulated phase-locked loop
A receiver is provided having a two-point-modulated phase-locked loop for the rapid scanning of the signal strength of a plurality of frequency channels. The two-point modulation includes a modulation of a frequency gain by an oscillator in the phase-locked loop and a modulation of a frequency division by a divider in the phase-locked loop.
Synchronization of receiver and transmitter local oscillators for ranging applications
A system and method for accurately determining a distance between two network devices using a Channel Sounding application is disclosed. The network devices each guarantee a fixed phase relationship between the transmit circuit and the receive circuit. In one embodiment, this is achieved by incorporating the divider within the phase locked loop. The divider may have a reset, such that it can be initialized to a predetermined state. Further, by utilizing a divider disposed within the phase locked loop with a reset, the quadrature signal generator is guaranteed to output clocks for the transmit circuit and the receive circuit that have a constant phase relationship.
Wideband multiphase transmitter with two-point modulation
The present disclosure is directed a wideband multiphase transmitter with two-point modulation. A transmitter includes a control circuit configured to receive a source signal having amplitude and phase components. Using the phase component, the control circuit generates a frequency control signal and a phase jump signal. The transmitter further includes a phase conversion circuit configured to generate a first phase-modulated signal using the phase component and the frequency control signal. The phase conversion circuit is also configured to adjust the phase of the first phase-modulated signal using the phase jump signal. The first phase-modulate signal and the amplitude component are provided to an amplifier, which generates a transmit signal based thereon.
Phase modulator having fractional sample interval timing skew for frequency control input
An example method in accordance with some embodiments includes: determining an output frequency control word (FCW) having a plurality of bits, the output FCW being configured to control an oscillator, the oscillator including a plurality of capacitor banks, the plurality of capacitor banks respectively corresponding to the plurality of bits of the output FCW; storing the output FCW in a clocked delay cell; providing an input clock to the clocked delay cell, wherein the input clock is provided to delay the output FCW by an amount of delay; and, in accordance with the input clock, releasing the delayed output FCW from the clocked delay cell, and respectively applying the plurality of bits of the delayed output FCW to the plurality of capacitor banks of the oscillator.