Radio communication system and wireless communication device

• US 20070024444A1
• Filed: 08/04/2004
• Published: 02/01/2007
• Est. Priority Date: 08/11/2003
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Fukuda, Kunio
• Granted Patent: US 7,986,234 B2
• Time in Patent Office: Days
• US Class Current: 340/572.100
• CPC Class Codes: G06K 19/0701 at least one of the integrated circuit chips comprising an arrangement for power management
• 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

A low consumption power is realized in a communication type that a ratio of transmission between apparatus limited to a relatively short distance occupies most of communications. Upon reception of transmission data constituted of a bit series, a wireless transmission module unit performs an on/off operation of an antenna switch connected to an antenna, in accordance with a bit image of the transmission data, and transmits, by a back scattering scheme, the transmission data as reflected radio waves of radio waves from a transmission destination generated by a change in an antenna load impedance. The antenna switch is generally made of a gallium arsenide IC, its consumption power is several 10 μW or less, and it becomes possible to realize ultra low consumption wireless image transmission.

Claims

1. A wireless communication system for data transmission by radio waves between a data supply source apparatus and a data provided destination apparatus, characterized in that:

the data supply source apparatus has an RFID (Radio Frequency Identification) tag function that transmits data by a back scattering scheme by absorbing or reflecting external radio waves in accordance with a bit string of the data through an on/off control of an antenna switch to make an antenna in a terminated state or an open state; and

the data provided destination apparatus has a reader function that transmits radio waves in a predetermined frequency band and reads data of an RFID tag in accordance with reflected waves.

2. The wireless communication system recited in claim 1, characterized in that:

the data provided destination apparatus transmits a non-modulated carrier or a modulated control signal, and the data supply source apparatus transmits data by absorbing or reflecting external radio waves on a basis of termination control of the antenna; and

the data provided destination apparatus receives the data on a basis of presence/absence of reflected waves from the supply source apparatus.

3. The wireless communication system recited in claim 1, characterized in that:

the data provided destination apparatus has means for storing or reproducing data received from the data supply source apparatus.

4. The wireless communication system recited in claim 1, characterized in that:

the data provided destination apparatus receives the data on a basis of presence/absence of reflected waves from the supply source apparatus, performs error detection, and transmits an error detection result in a form of a control signal made of an ASK, PSK or FSK modulation wave, and the data supply source apparatus demodulates the control signal at the reception unit and demodulation unit to perform re-transmission control.

5. The wireless communication system recited in claim 1, characterized in that:

the data supply source apparatus having the photographing means is remotely controlled by a command in the control signal transmitted from the data provided destination apparatus.

6. A wireless communication apparatus for transmitting data, characterized by comprising:

a signal processing unit for processing transmission data; and

a wireless transmission module including an antenna, an antenna switch and an antenna load,

wherein data is transmitted by a back scattering scheme by absorbing or reflecting external radio waves in accordance with a bit string of the data through an on/off control of the antenna switch to make the antenna in a terminated state or an open state in accordance with a bit image of the transmission data.

7. The wireless communication apparatus recited in claim 6, characterized in that the wireless transmission module unit further has a reception unit and a demodulation unit for receiving and processing an external control signal made of ASK, PSK or FSK modulation waves.

8. The wireless communication apparatus recited in claim 6, characterized by further comprising:

transmission data generating means for generating the transmission data.

9. The wireless communication apparatus recited in claim 6, characterized by further comprising:

photographing means for photographing an image such as a still image and a moving image through a camera function,

wherein the signal processing unit processes a photographed image by the photographing means as the transmission data.

10. The wireless communication apparatus recited in claim 6, characterized by further comprising:

external interface means for connecting an external apparatus for supplying the transmission data.