Other

Shenzhen Goodix Technology Co., Ltd.

Si-ware Systems

Nabil Sinoussi

Ayman Ahmed

Mohamed Weheiba

Ahmed Sayed Abbas Metawea

Ahmed A Helmy

Ahmed H A Razek

Michael Sherif Sobhy Nagib

Bassel Hanafi

Techniques are described for frequency-division-coordination of automatic power control (APC) in a transceiver of a near-field reader. Such frequency-division-coordinated APC (FDC-APC) can enable continuous APC updates concurrent with communication frames to achieve field strength specifications without conventional degradations in communication reliability. For example, a transceiver implements a FDC-APC loop that received a detuning signal from signals received and/or transmitted over a near-field communication link, generates an error signal by comparing the detuning signal with a reference detuning level, and updates a power control signal according to an update frequency (e.g., corresponding to a APC loop bandwidth) that is a function of at least a filter frequency profile and is out-of-band with respect to a modulation frequency band. Modulated signals can be transmitted over the near-field communication link according to variable power settings controlled to the power control signal.

Frequency-division-coordinated automatic power control for near-field communication

A substantially temperature-independent LC-based oscillator uses bias control techniques. Temperature independence may be achieved by controlling the harmonic frequency content of the output of the oscillator by controlling the amplitude. Amplitude control may be achieved by inserting a control mechanism in the feedback loop of the oscillator.

Method and apparatus to control the LC tank temperature null characteristic in a highly stable LC oscillator

Oscillators are described that have a highly stable output frequency versus the variation of supply voltage and different operating conditions such as temperature. The concepts are broadly applicable to various types of oscillators. The highly stable output is achieved with the use of self biasing loops. The circuits associated with providing constant harmonic output current can be used with the concept of a phi-null oscillator to further stabilize the output frequency.

Self-biased amplitude-controlled oscillator with constant harmonic content

An LC oscillator tank that generates a tank oscillation at a phase substantially equal to a temperature null phase. The oscillator further includes frequency stabilizer circuitry coupled to the LC oscillator tank to cause the LC oscillator tank to operate at the temperature null phase. In one aspect of the disclosure, a feedback loop may split the output voltage of the LC tank into two voltages having different phases, where each voltage is independently transformed into a current through programmable transconductors, The two currents may be combined to form a resultant current which is then applied to the LC tank. The phase of the resultant current is such that the LC tank operates at an impedance condition that achieves frequency stability across temperature.

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Cairo, Egypt

Nabil Sinoussi