US 2009/0289767 A1 · INTERROGATING DEVICE, RFID INTERROGATOR, AND RFID INTERROGATING METHOD

Abstract

An RFID interrogator includes a data transmitting unit, a data receiving unit, a tag-reception SINR estimating unit, and a transmission controlling unit. The data transmitting unit transmits a transmission signal to an electronic tag. The data receiving unit receives from the electronic tag a response signal in response to the transmission signal within a predetermined time after the transmission signal is transmitted. The tag-reception SINR estimating unit estimates an SINR value related to reception on the electronic tag side as a tag-reception SINR estimation value based on the response signal. The transmission controlling unit variably controls a modulation index of the transmission signal so that the tag-reception SINR estimation value is a reception-allowable predetermined SINR value.

Claims20

Dependent claims

An interrogating device that transmits a signal to an electronic tag that generates a response signal by controlling a reflectivity at a reception end to at least a first reflectivity and a second reflectivity higher than the first reflectivity, the interrogating device comprising:

a transmitting unit that transmits a transmission signal to the electronic tag;
a receiving unit that receives a response signal in response to the transmission signal from the electronic tag;
an extracting unit that extracts, from the response signal, a signal portion to which the second reflectivity is applied based on strength of a reception signal;
and
an estimating unit that estimates reception quality in the electronic tag based on the signal portion extracted by the extracting unit.

2 more elements

A radio frequency identification (RFID) interrogator comprising:

a transmitting unit that transmits a transmission signal to an electronic tag;
a receiving unit that receives from the electronic tag a response signal in response to the transmission signal within a predetermined time after the transmission signal is transmitted from the transmitting unit;
a tag-reception SINR estimating unit that estimates a signal to interference plus noise ratio (SINR) value related to reception by the electronic tag as a tag-reception SINR estimation value based on the response signal received by the receiving unit from the electronic tag;
and
a transmission controlling unit that controls the transmitting unit to variably control a modulation index of the transmission signal so that the tag-reception SINR estimation value estimated by the tag-reception SINR estimating unit is a reception-allowable predetermined SINR value.

2 more elements

Dependencies are inferred from the claim text.

Interrogating device, rfid interrogator, and rfid interrogating method

Life of this patent

Interrogating device, rfid interrogator, and rfid interrogating method

Life of this patent

Abstract

Claims20