Broadcom Corporation

Avago Technologies General IP (singapore) Pte. Ltd.

Manolis Frantzeskakis

Henrik Tholstrup Jensen

Yushi Tian

Shengyang Xu

Jianhua Gan

Dong-U Lee

Jianfeng Shi

Divyanshu Jain

Georgios Srikas

In some aspects, the disclosure is directed to methods and systems for carrier synchronization in active load modulation for near field communications. A broadcast carrier is received from a remote device and mixed with a locally-generated carrier and modulated data. A carrier synchronization circuit synchronizes the locally-generated carrier with the broadcast carrier based on an identified phase error from a double Cartesian-to-polar mapping of the mixed locally-generated carrier and broadcast carrier. In some implementations, the system also includes a modulation suppression circuit for providing unmodulated carrier signals to the carrier synchronization circuit or suppressing modulation distortion to maintain frequency and phase tracking despite the presence of data.

Carrier synchronization appropriate for ALM NFC data transmission

The present disclosure is directed to a method and apparatus for providing an output oscillating signal at a desired frequency. In at least one example, the apparatus includes a weak inversion structure configured to set a small reference current. A current mirror configured to provide a replica current based on the small reference current and a tuning word. A ring oscillator is configured to be powered by a supply at a voltage determined based on the replica current. The tuning word is adjustable to change the voltage such that the ring oscillator provides the output oscillating signal at the desired frequency.

Frequency synthesis using a ring oscillator

Growing community of inventors

Ilioupolis, Greece

Manolis Frantzeskakis