Reducing power consumption for connection establishment in near field communication systems

Patent metadata

Field	Value
Publication number	US-8942628-B2
Application number	US-201213664342-A
Country	US
Kind code	B2
Filing date	Oct 30, 2012
Priority date	Nov 28, 2011
Publication date	Jan 27, 2015
Grant date	Jan 27, 2015

Abstract

A method and apparatus for reducing power consumption associated with establishing a connection in a near field communication system is disclosed. According to some embodiments, when requesting an active mode NFC connection, the initiator device can selectively extend transmission of its NFC carrier signal by an extended period of time after transmitting a polling command to the target device. The extended period of time allows the target device additional time to stabilize its clock signal and transmit its own NFC carrier signal back to the initiator device. As a result, the initiator device may wait to enable its NFC clock generator until after receiving a polling command that requests the active mode NFC session. In this manner, when the initiator device requests a passive mode NFC connection, the target device may not enable its NFC clock generator, thereby reducing power consumption.

First claim

What is claimed is:

1. A method of operating a target device to establish a near-field communication (NFC) connection with an initiator device, the method comprising:
receiving a first carrier signal from the initiator device, wherein the first carrier signal includes a polling command;
determining whether the polling command requests an active communication mode or a passive communication mode; and
selectively enabling an NFC clock generator in the target device in response t…

Assignees

• Qualcomm Inc

Inventors

• Haverinen Anssi Kaleva

Classifications

• Y02D30/70

  Cross-Sectional Technologies · mapped topic

• H04B5/48 Primary

  Electricity · mapped topic