Semiconductor device and position detecting method using the semiconductor device

• US 20070252208A1
• Filed: 04/17/2007
• Published: 11/01/2007
• Est. Priority Date: 04/28/2006
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Koyama, Jun, Yamazaki, Shunpei
• Granted Patent: US 8,364,077 B2
• Time in Patent Office: Days
• US Class Current: 257/347
• CPC Class Codes: G01S 5/0027 of actual mobile position, i.e. position determined on mobile
• CPC Class Codes: G01S 5/0221 Receivers
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer

Abstract

An object of the present invention is to solve a problem of a conventional semiconductor device in that although information such as whether the semiconductor device exists in a predetermined space and information on an ID and the like included in the semiconductor device can be obtained, a position where the semiconductor is located in the predetermined space cannot be identified. The semiconductor device includes a signal sorting portion which sorts a signal based on a signal output from the outside and a signal detecting portion for detecting the signal output from the outside. In a structure of the semiconductor device including the signal sorting portion and the signal detecting portion, a position detecting system is developed base on signals from a plurality of interrogators.

Claims

1. A semiconductor device comprising:

an antenna circuit receiving signals from a plurality of interrogators;

a signal sorting portion for sorting the signals from the plurality of interrogators; and

a signal detecting portion for detecting intensity of the signals sorted by the signal sorting portion.

2. A semiconductor device according to claim 1, wherein the signals from the plurality of interrogators are different in frequency.

3. A semiconductor device according to claim 1,

wherein the signal sorting portion includes a frequency mixer, a bandpass filter, an oscillation circuit, and an oscillation frequency control circuit;

and

wherein signals with different frequency, which are generated in the frequency mixer based on the signals from the plurality of interrogators and a signal from the oscillation circuit, are output through the bandpass filter, so that the signals from the plurality of interrogators are sorted.

4. A semiconductor device according to claim 3, wherein an amplifier circuit for amplifying a signal transmitted to and received from the antenna circuit is included.

5. A semiconductor device according to claim 1, wherein the signal detecting portion includes a demodulation circuit and a baseband signal processing circuit which are for decoding the signals from the plurality of interrogators, which are sorted by the signal sorting portion.

6. A semiconductor device according to claim 1,

wherein the signal detecting portion includes a rectifier circuit, an A/D conversion circuit, and a central processing unit;

and

wherein the signal detecting portion inputs a signal output from the rectifier circuit to the central processing unit through the A/D conversion circuit, and detects the intensity of the signals sorted by the signal sorting portion.

7. A position detecting method for detecting position information of a semiconductor device, comprising the steps of:

receiving signals from a plurality of interrogators by an antenna circuit;

sorting the signals received by the antenna circuit by a signal sorting portion;

detecting intensity of the signal sorted by the signal sorting portion by a signal detecting portion; and

detecting intensity of signals from the plurality of interrogators and transmitting information on the intensity of the signals from the plurality of interrogators to one of the plurality of interrogators.

8. A position detecting method according to claim 7, wherein the signals from the plurality of interrogators are different in frequency.

9. A position detecting method according to claim 7,

wherein the signal sorting portion includes a frequency mixer, a bandpass filter, an oscillation circuit, and an oscillation frequency control circuit;

and

wherein signals with different frequency, which are generated in the frequency mixer based on the signals from the plurality of interrogators and a signal from the oscillation circuit, are output through the bandpass filter, so that the signals from the plurality of interrogators are sorted.

10. A position detecting method according to claim 7,

wherein the signal detecting portion includes a demodulation circuit and a baseband signal processing circuit;

and

wherein the signals from the plurality of interrogators, which are sorted by the signal sorting portion are decoded.

11. A position detecting method according to claim 7,

wherein the signal detecting portion includes a rectifier circuit, an A/D conversion circuit, and a central processing unit;

and

wherein the signal detecting portion detects intensity of the signal sorted by the signal sorting portion when a signal output from the rectifier circuit is output to the central processing unit through the A/D conversion circuit.

12. A position detecting method according to claim 11, wherein the central processing unit calculates a distance between the semiconductor device and the interrogator, based on intensity of the signal input to the central processing unit.

13. A semiconductor device comprising:

an antenna circuit receiving signals;

a signal sorting portion for sorting at least a first signal and a second signal received by the antenna circuit; and

a signal detecting portion for detecting intensity of signals sorted by the signal sorting portion.

14. A semiconductor device according to claim 13, wherein the first signal and the second signal are different in frequency.

15. A driving method of a semiconductor device, comprising the steps of:

receiving signals by an antenna circuit;

sorting at least of a first signal and a second signal received by the antenna circuit by a signal sorting portion;

detecting intensity of the signals sorted by the signal sorting portion by a signal detecting portion; and

transmitting information on the intensity of the signals detected by the signal detecting portion.

16. A driving method of a semiconductor device according to claim 15, wherein the first signal and the second signal are different in frequency.

17. A semiconductor device comprising:

an antenna circuit;

an oscillation circuit;

a frequency mixer where signals received by the antenna circuit and a signal output from the oscillation circuit are input into;

a bandpass filter;

a rectifier circuit where the signal output from the frequency mixer is input into through the band pass filter;

an A/D conversion circuit where a voltage output from the rectifier circuit is input into;

a central processing unit where a signal output from the A/D conversion circuit is input into; and

an oscillation frequency control circuit where a signal output from the central processing unit is input into, wherein the oscillation frequency control circuit controls a oscillation frequency of the oscillation circuit.