A system, method and apparatus for simultaneously minimizing power and latency in a scan for advertisement packets from one or more peripheral devices in a Bluetooth Low Energy (BLE) frequency band having a number of advertisement channels. A receiver front end receives BLE signals, and a local oscillator (LO) generator has an output frequency that is sequentially tuned to a frequency of each of the advertisement channels. An energy detector monitors signal energy on each of the advertisement channels in sequence, and when the signal energy exceeds a threshold, fixes the output frequency of the LO generator to that advertisement channel. An automatic gain controller controls a gain of the signal on the one of the plurality of advertisement channels to generate a controlled gain signal, and a correlator correlates the controlled gain signal with an advertisement packet on the one of the advertisement channels.

A system, method and apparatus for simultaneously minimizing power and latency in a scan for advertisement packets from one or more peripheral devices in a Bluetooth Low Energy (BLE) frequency band having a number of advertisement channels. A receiver front end receives BLE signals, and a local oscillator (LO) generator has an output frequency that is sequentially tuned to a frequency of each of the advertisement channels. An energy detector monitors signal energy on each of the advertisement channels in sequence, and when the signal energy exceeds a threshold, fixes the output frequency of the LO generator to that advertisement channel. An automatic gain controller controls a gain of the signal on the one of the plurality of advertisement channels to generate a controlled gain signal, and a correlator correlates the controlled gain signal with an advertisement packet on the one of the advertisement channels.

A non-contact phase-locked and self-injection-locked vital sign sensor includes a self-oscillating voltage-controlled frequency-adjustable radiating element and a phase-locked loop. The self-oscillating voltage-controlled frequency-adjustable radiating element is used for transmitting an oscillation signal to an organism and for receiving a corresponding reflected signal from the organism to be posed at a self-injection-locked state, the oscillation signal being tuned by a vital sign of the organism to form a frequency-tuned signal. The phase-locked loop is used for demodulating the frequency-tuned signal to obtain a corresponding vital signal of the organism. By comparing the oscillation signal frequency-eliminated and outputted from the self-oscillating voltage-controlled frequency-adjustable radiating element with a reference signal, a corresponding comparison result is used to vary a phase of the frequency-divided oscillation signal for maintaining the same phase of the reference signal. Thereupon, the oscillation frequency can be stabilized, and the measurement sensitivity can be enhanced.

A non-contact phase-locked and self-injection-locked vital sign sensor includes a self-oscillating voltage-controlled frequency-adjustable radiating element and a phase-locked loop. The self-oscillating voltage-controlled frequency-adjustable radiating element is used for transmitting an oscillation signal to an organism and for receiving a corresponding reflected signal from the organism to be posed at a self-injection-locked state, the oscillation signal being tuned by a vital sign of the organism to form a frequency-tuned signal. The phase-locked loop is used for demodulating the frequency-tuned signal to obtain a corresponding vital signal of the organism. By comparing the oscillation signal frequency-eliminated and outputted from the self-oscillating voltage-controlled frequency-adjustable radiating element with a reference signal, a corresponding comparison result is used to vary a phase of the frequency-divided oscillation signal for maintaining the same phase of the reference signal. Thereupon, the oscillation frequency can be stabilized, and the measurement sensitivity can be enhanced.

A Sagnac loop coherent phase modulated RF photonic link employing an ACP-OPLL linear phase demodulator was presented. This structure demonstrated stable signal transmission over a 1-km long coherent RF photonic link.

A Sagnac loop coherent phase modulated RF photonic link employing an ACP-OPLL linear phase demodulator was presented. This structure demonstrated stable signal transmission over a 1-km long coherent RF photonic link.

A quadrature detector subjects a received signal to quadrature detection and outputs a base band signal. A direct current component measurement circuit measures a magnitude of a direct current component included in the base band signal from the quadrature detector. A first HPF and a second HPF reduce the direct current component included in the base band signal from the quadrature detector. A demodulator demodulates the base band signal output from the first HPF and the second HPF. A controller exercises control to attenuate a level of the received signal input to the quadrature detector when the magnitude of the direct current component measured by the direct current component measurement circuit is equal to or larger than a threshold value.

Many embodiments of the invention include stacked power amplifier configurations that include control circuitry for sensing the operational characteristics of the power amplifiers and adjusting the current drawn by one or more of the power amplifiers to prevent any of the power amplifiers from experiencing over voltage stresses and/or to increase the operational efficiency of the power amplifiers.

Many embodiments of the invention include stacked power amplifier configurations that include control circuitry for sensing the operational characteristics of the power amplifiers and adjusting the current drawn by one or more of the power amplifiers to prevent any of the power amplifiers from experiencing over voltage stresses and/or to increase the operational efficiency of the power amplifiers.

Disclosed are systems, methods, and structures for DSP-free coherent receiver architectures applicable for short-reach optical links. Operationally, a received optical signal is down-converted by mixing it with a local oscillator (LO) laser signal using a 90-degree hybrid followed by balanced photodiodes. Other receiver functions are performed using analog signal processing thereby avoiding power-hungry, high-speed analog-to-digital converters and high-speed digital signal processing. Carrier phase recovery is performed by an electrical phase-locked loop employing a multiplier-free phase estimator stage thatwhile designed for quaternary phase-shift keying signalsmay be employed in designs exhibiting higher modulation formats. Since carrier phase recovery is performed in the electrical domain, LO laser frequency modulation or LO laser integration is not employed. Polarization demultiplexingif employedmay be performed by the addition of an optical polarization controller prior to the hybrid and may advantageously be realized by cascading multiple phase shifters driven by low-speed circuitry.