System for Sensing a Physical Property in a Plurality of Scanning Positions

• US 20080203162A1
• Filed: 04/04/2006
• Published: 08/28/2008
• Est. Priority Date: 04/14/2005
• Status: Abandoned Application

• Current Assignee: NXP B.V. (NXP Semiconductors NV)
• Original Assignee: NXP B.V. (NXP Semiconductors NV)
• Inventors: Fontijn, Wilhelmus Franciscus, Dijkstra, Eelco
• Application Number:
  US11/911,470
• Publication Number:
  US 20080203162A1
• Time in Patent Office: Days
• US Class Current: 235/440
• CPC Class Codes: G01S 13/878 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S13/874 takes precedence
• 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
• CPC Class Codes: G06K 7/10079 the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions
• CPC Class Codes: G06K 7/10346 the antenna being of the far field type, e.g. HF types or dipoles
• CPC Class Codes: G06K 7/10356 using a plurality of antennas, e.g. configurations including means to resolve interference between the plurality of antennas

Abstract

A system for sensing a physical property allocated to scanning positions (P1-P5, P11-P44, Pijk) comprises sensors (A1-A5, B) adapted to sense the physical property within sensing regions (AR1-AR5, BR1-BR2, C1-C3, D1-D3, E1-E3, F1-F4, G1-G3, H1-H4), wherein the sensing regions (AR1-AR5, BR1-BR2, C1-C3, D1-D3, E1-E3, F1-F4, G1-G3, H1-H4) are arranged such that each of them sweeps at least one scanning position (P1-P5, P11-P44, Pijk) and sensing regions (AR1-AR5, BR1-BR2, C1-C3, D1-D3, E1-E3, F1-F4, G1-G3, H1-H4) are superposed on one another at least at one scanning position (P1-P5, P11-P44, Pijk), so that each scanning position is swept by a unique pattern of sensing regions (AR1-AR5, BR1-BR2, C1-C3, D1-D3, E1-E3, F1-F4, G1-G3, H1-H4), wherein the following condition is fulfilled:

log₂(n)≦i<x·n^1/x

• • with
    • i . . . number of sensing regions
    • n . . . number of scanning positions
    • x . . . number of spatial dimensions in which the arrangement of scanning positions extend.

Claims

1. A system for sensing a physical property allocated to scanning positions, comprising sensors adapted to sense the physical property within sensing regions, wherein the sensing regions are arranged such that each of said regions sweeps at least one scanning position, the sensing regions being superposed on one another at least in one scanning position such that each scanning position is swept by a unique pattern of sensing regions while the following condition is fulfilled:

log₂(n)≦

i≦

x·

n^1/x

with

i . . . number of sensing regions

n . . . number of scanning positions

x . . . number of spatial dimensions in which the arrangement of said scanning positions

extends.

2. The sensing system as claimed in claim 1, wherein the following condition is fulfilled:

log₂(n)≦

i≦

1+log₂(n)

with

i . . . number of sensing regions

n . . . number of scanning positions

3. The sensing system as claimed in claim 1, wherein the physical property comprises identity codes of RFID transponders of objects, and the sensors are configured as antennas designed for reading the identity codes of the RFID transponders.

4. The sensing system as claimed in claim 1, wherein the physical properties comprise luminous intensity, luminous flux, quantity of light, wavelength or color, mass, force, pressure, flow rate, radioactivity, temperature, electric field strength, magnetic flux, electrical resistance, inductance, capacity, current, or voltage, and the sensors are configured to sense said physical properties.

5. The sensing system as claimed in claim 1, wherein the sensing results of the sensing regions are transmitted via sensing signals, and wherein the sensing signals are fed to a detector that is adapted to allocate each sensing signal to a different digit of a position code.

6. The sensing system as claimed in claim 5, wherein the detector is adapted to discriminate binary values from the sensing signals and to allocate the binary values to the respective digits of the position code.

7. The sensing system as claimed in claim 5, wherein the detector is adapted to allocate the sensing signals as discrete numbers to the respective digits of the position code.

8. The sensing system as claimed in claim 5, wherein the sensing signals are fed to a multiplexer, and the output of the multiplexer is fed to the detector.

9. The sensing system as claimed in claim 1, wherein a sensor with a sensing region is provided that sweeps the entirety of scanning positions.