Broadcom Corporation

Avago Technologies General IP (Singapore) Pte. Ltd.

Dong-U Lee

Shengyang Xu

Divyanshu Jain

Jianhua Gan

Manolis Frantzeskakis

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

A first near field communication (NFC) device or a first NFC-enabled device utilizes a feedback based approach to allow for dynamic adjusting of one or more operating characteristics. The feedback based approach can be a direct feedback based approach or an indirect feedback based approach. In the direct feedback based approach, a second NFC device or a second NFC-enabled device can communicate information to the first NFC device or the first NFC-enabled device to cause the first NFC device or the first NFC-enabled device to dynamically adjust the one or more operating characteristics. In the indirect feedback based approach, the first NFC device or the first NFC-enabled device can dynamically adjust the one or more operating characteristics in response to the non-occurrence of an event, such as receiving a response command from the second NFC device or the second NFC-enabled device to provide an example.

Feedback-based adaptive load modulation (ALM) for a near field communication (NFC) device

A first near field communication (NFC) device is disclosed that synchronizes a first carrier wave of the first NFC device to a second carrier wave of a second NFC device. The first NFC device observes a magnetic field having the first carrier wave modulated with information corresponding to the first NFC device and the second carrier wave modulated with information corresponding to the second NFC device. The first NFC device isolates the information corresponding to the second NFC device from the combined sequence of information to determine a frequency error and/or a phase error between the carrier waves. Finally, the first NFC device adjusts the frequency of the first carrier wave in accordance with the first frequency error and/or the phase of the first carrier wave in accordance with the first phase error to synchronize the carrier waves.

Growing community of inventors

Irvine, CA, United States of America

Dong-U Lee