Control method for high-frequency radio equipment and high-frequency radio system

• US 20060125601A1
• Filed: 10/26/2005
• Published: 06/15/2006
• Est. Priority Date: 10/27/2004
• Status: Active Grant

• Current Assignee: Nihon Dempa Kogyo Company Limited
• Original Assignee: Nihon Dempa Kogyo Company Limited
• Inventors: Onishi, Naoki
• Granted Patent: US 7,489,949 B2
• Time in Patent Office: Days
• US Class Current: 340/5.720
• CPC Class Codes: G07C 2209/61 Signal comprising different frequencies, e.g. frequency hopping
• CPC Class Codes: G07C 9/00309 operated with bidirectional data transmission between data carrier and locks
• CPC Class Codes: H04B 7/0805 with single receiver and antenna switching H04B7/0822 takes precedence
• CPC Class Codes: H04B 7/086 using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming
• CPC Class Codes: H04J 13/00 Code division multiplex systems for frequency hopping H04B1/713

Abstract

A control method for a high-frequency radio equipment and a high-frequency radio equipment system in spread spectrum radio data communication are provided which are interference-tolerant and can maintain transmission quality with improved receiving sensitivity. A high-frequency radio equipment system provided with, in a base station, an antenna part comprised by a plurality of antennas, a radio part for amplifying a received signal, band-limiting and down-converting it to an intermediate frequency, a signal processing part for carrier-demodulating the signal inputted from the radio part, demodulating the signal which was despread-spectrum processed and synchronized and decoding the received data, an antenna control part for determining a code error rate for the received data inputted from the signal processing part, forming an appropriate antenna pattern based on the error rate and outputting a signal for controlling an antenna switching part according to the information of the antenna pattern.

Claims

1. A control method for high-frequency radio equipment comprising the steps of:

receiving a signal of an extremely low radio wave which is spread-spectrum modulated;

determining an state of communication environment determined based on the received data by despread-spectrum demodulation; and

adjusting synthesized directivity of antennas arranged in plural according to the state of the communication environment.

2. A control method for high-frequency radio equipment according to claim 1,

wherein the communication environment state is determined using a code error rate of the received data.

3. A control method for high-frequency radio equipment according to claim 1,

wherein adjustment of the synthesized directivity of the antenna is realized by forming an antenna pattern specifying an antenna for reception from a plurality of antennas and by selecting an antenna according to the formed antenna pattern.

4. A control method for high-frequency radio equipment according to claim 2,

wherein adjustment of the synthesized directivity of the antenna is realized by forming an antenna pattern specifying an antenna for reception from a plurality of antennas and by selecting an antenna according to the formed antenna pattern.

5. A control method for high-frequency radio equipment according to claim 1,

wherein an identifier contained in the received data is checked, and only when the identifier matches an identifier stored on the receiving side, the determination of the communication environment state is made.

6. A control method for high-frequency radio equipment according to claim 2,

wherein an identifier contained in the received data is checked, and only when the identifier matches an identifier stored on the receiving side, the determination of the communication environment state is made.

7. A control method for high-frequency radio equipment according to claim 1,

wherein, after adjustment of the synthesized directivity of the antenna, when a spreading ratio is not at the lower limit in a predetermined range, information instructing a decrease of the spreading ratio for the subsequent received frames is sent to the transmission side, and the receiving operation is performed at the decreased spreading ratio on the receiving side.

8. A control method for high-frequency radio equipment according to claim 2,

wherein, after adjustment of the synthesized directivity of the antenna, when a spreading ratio is not at the lower limit in a predetermined range, information instructing a decrease of the spreading ratio for the subsequent received frames is sent to the transmission side, and the receiving operation is performed at the decreased spreading ratio on the receiving side.

9. A control method for high-frequency radio equipment according to claim 1,

wherein, after adjustment of synthesized directivity of the antenna, when a spreading ratio is not at the upper limit in a predetermined range, information instructing an increase of the spreading ratio for the subsequent received frames is sent to the transmission side, and the receiving operation is performed at the increased spreading ratio on the receiving side.

10. A control method for high-frequency radio equipment according to claim 2,

wherein, after adjustment of synthesized directivity of the antenna, when a spreading ratio is not at the upper limit in a predetermined range, information instructing an increase of the spreading ratio for the subsequent received frames is sent to the transmission side, and the receiving operation is performed at the increased spreading ratio on the receiving side.

11. A high-frequency radio equipment system provided with a base station for receiving an extremely weak radio wave from a portable equipment in the spread spectrum communication method, the base station comprises:

an antenna part provided with a plurality of antennas;

a radio part for amplifying and band-limiting the extremely weak radio wave taken in from the antenna part, down-converting and amplifying it to an intermediate frequency band;

a signal processing part for carrier-demodulating the signal inputted from the radio part, demodulating the signal which was despread-spectrum processed and synchronized, and decoding the received data;

an antenna switching part for adjusting directivity at the antenna part by selecting a specific antenna; and

an antenna control part for forming an antenna pattern at the antenna switching part according to a code error rate for the data of the received signal obtained at the signal processing part.

12. A high-frequency radio equipment system according to claim 11,

wherein the antenna control part is provided with an antenna status table storing an antenna pattern corresponding to a specific directivity in advance and the current directivity, and the antenna status table is referred to so as to determine an antenna pattern based on the code error rate of the received data and the current directivity.

13. A high-frequency radio equipment system according to claim 11,

wherein the antenna control part forms an antenna pattern only when an identifier contained in the received data matches the identifier stored in advance.

14. A high-frequency radio equipment system according to claim 12,

wherein the antenna control part forms an antenna pattern only when an identifier contained in the received data matches the identifier stored in advance.

15. A high-frequency radio equipment system according to claim 11,

wherein the antenna control part adjusts the directivity at the antenna part by forming an antenna pattern and then, when the spreading ratio is not at a lower limit within a predetermined range, information instructing a decrease of the spreading ratio for the subsequent received frames is sent to the portable equipment and a control signal is outputted so that the receiving operation is performed at the decreased spreading ratio at the radio part and the signal processing part of the base station.

16. A high-frequency radio equipment system according to claim 12,

wherein the antenna control part adjusts the directivity at the antenna part by forming an antenna pattern and then, when the spreading ratio is not at a lower limit within a predetermined range, information instructing a decrease of the spreading ratio for the subsequent received frames is sent to the portable equipment and a control signal is outputted so that the receiving operation is performed at the decreased spreading ratio at the radio part and the signal processing part of the base station.

17. A high-frequency radio equipment system according to claim 11,

wherein the antenna control part adjusts the directivity at the antenna part by forming an antenna pattern and then, when the spreading ratio is not at an upper limit within a predetermined range, information instructing an increase of the spreading ratio for the subsequent received frames is sent to the portable equipment and a control signal is outputted so that the receiving operation is performed at the increased spreading ratio at the radio part and the signal processing part of the base station.

18. A high-frequency radio equipment system according to claim 12,

wherein the antenna control part adjusts the directivity at the antenna part by forming an antenna pattern and then, when the spreading ratio is not at an upper limit within a predetermined range, information instructing an increase of the spreading ratio for the subsequent received frames is sent to the portable equipment and a control signal is outputted so that the receiving operation is performed at the increased spreading ratio at the radio part and the signal processing part of the base station.

19. A high-frequency radio equipment system according to claim 11,

wherein the radio part uses a crystal filter for amplifying and band-limiting the extremely weak radio wave taken in from the antenna part, a crystal resonator for oscillating a high-frequency local signal for down-converting the band-limited signal to an intermediate frequency band, and the crystal filter and the crystal oscillator are mounted at portions of the operating environments where the temperature characteristic and secular change characteristic are substantially the same to each other.

20. A high-frequency radio equipment system according to claim 12,

wherein the radio part uses a crystal filter for amplifying and band-limiting the extremely weak radio wave taken in from the antenna part, a crystal resonator for oscillating a high-frequency local signal for down-converting the band-limited signal to an intermediate frequency band, and the crystal filter and the crystal oscillator are mounted at portions of the operating environments where the temperature characteristic and secular change characteristic are substantially the same to each other.