Systems and methods for detecting data collisions for a near field communication system
AssigneeQUALCOMM Incorporated
InventorsKoorosh Akhavan, RaviKiran Gopalan, Eunmo Kang, Le Nguyen Luong
Life of this patent
Estimating the term…
Abstract
In a wireless near field communication (NFC) system, a target, such as a smart card, can communicate with an initiator, such as a card reader, by load modulating a radio frequency (RF) signal generated by the initiator. When two or more targets load modulate the RF signal generated, “collisions” can occur with the load modulation. Apparatus and methods detect the presence or absence of collisions in a lower layer or physical layer and report the presence of detected collisions to an upper layer for further handling.
Claims28
An apparatus, comprising:
- a circuit configured to generate a first soft symbol and a second soft symbol, wherein values of the first soft symbol and the second soft symbol are at least indicative of a presence or absence of load modulation in a first portion and a second portion of a data symbol period of a near field communication signal;
- and
- a collision analyzer configured to determine whether or not a collision is present based at least partly on comparisons of the values of the first soft symbol and the second soft symbol with at least two different threshold levels.
An electronically-implemented method of detecting data collisions for a near field communication system, the method comprising:
- generating, by an electronic circuit, a first soft symbol and a second soft symbol, wherein values of the first soft symbol and the second soft symbol are at least indicative of a presence or absence of load modulation in a first portion and a second portion of a data symbol period of a near field communication signal;
- and
- determining whether or not a collision is present based at least partly on comparisons of the values of the first soft symbol and the second soft symbol with at least two different threshold levels.
An apparatus for detecting data collisions for a near field communication system, the apparatus comprising:
- a means for generating a first soft symbol and a second soft symbol, wherein values of the first soft symbol and the second soft symbol are at least indicative of a presence or absence of load modulation in a first portion and a second portion of a data symbol period of a near field communication signal;
- and
- a means for determining whether or not a collision is present based at least partly on comparisons of the values of the first soft symbol and the second soft symbol with at least two different threshold levels.
An apparatus for detecting data collisions induced for a near field communication system, the apparatus comprising:
- a processor;
- and
- a computer program executable by the processor the computer program embodied in a tangible, non-transitory computer-readable medium, wherein the computer program embodies a method comprising:
- generating a first soft symbol and a second soft symbol, wherein values of the first soft symbol and the second soft symbol are at least indicative of a presence or absence of load modulation in a first portion and a second portion of a data symbol period of a near field communication signal;
- and
- determining whether or not a collision is present based at least partly on comparisons of the values of the first soft symbol and the second soft symbol with at least two different threshold levels.
Dependencies are inferred from the claim text.