RADIO RECEIVING APPARATUS AND RADIO RECEIVING METHOD

• US 20090154526A1
• Filed: 09/26/2006
• Published: 06/18/2009
• Est. Priority Date: 09/26/2005
• Status: Active Grant

• Current Assignee: Panasonic Electric Works Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Asahi Matsushita Electric Works Ltd. (Panasonic Holdings Corporation)
• Inventors: Hayashi, Masanori, Sugino, Satosi, Okita, Atsushi
• Granted Patent: US 7,940,863 B2
• Time in Patent Office: Days
• US Class Current: 375/130
• CPC Class Codes: H04B 1/719 Interference-related aspects

Abstract

A radio receiving apparatus of the present invention is for receiving a radio signal having pulsating signals occurring at specific periods, wherein the radio receiving apparatus corrects signal levels received during communication in individual regions into which each of the aforementioned periods is divided based on signal levels received in the individual regions under conditions where the radio signal is not received. As a result of this correction, the radio receiving apparatus of the present invention can decrease the influence of noise having periodicity and improve reliability of communication.

Claims

1. A radio receiving apparatus for receiving a radio signal having pulsating signals occurring at specific periods, said radio receiving apparatus being characterized by comprising:

a receiver portion for receiving said radio signal;

a regional level acquirer for acquiring a signal level obtained by said receiver portion in each of plural regions into which each of said periods is divided;

a regional level storage for storing signal levels acquired by said regional level acquirer in said individual regions under conditions where said radio signal is not received by said receiver portion for said individual regions;

a corrector portion for correcting the signal levels in said individual regions received by said receiver portion based on the signal levels in said individual regions stored in said regional level storage, respectively; and

a demodulator portion for demodulating said radio signal according to the signal levels in the individual regions corrected by said corrector portion.

2. The radio receiving apparatus as recited in claim 1, said radio receiving apparatus being characterized in that said regional level acquirer acquires said signal levels in said plural regions while successively offsetting the regions in which said signal levels are acquired.

3. The radio receiving apparatus as recited in claim 1, said radio receiving apparatus being characterized in that said regional level acquirer acquires the signal levels in said individual regions over said plural periods, calculates average values of the signal levels thus acquired in time durations corresponding to said individual regions in each of said plural periods, and causes said regional level storage to store the average values calculated for the individual time durations as the signal levels in said individual regions.

4. The radio receiving apparatus as recited in claim 1, said radio receiving apparatus being characterized in that said corrector portion performs said correction by subtracting the signal levels in said individual regions stored in said regional level storage from the signal levels in said individual regions received by said receiver portion, respectively.

5. The radio receiving apparatus as recited in claim 1, said radio receiving apparatus being characterized in that said corrector portion performs said correction by adding differences between a preset reference value and the signal levels in said individual regions stored in said regional level storage to the signal levels in said individual regions received by said receiver portion, respectively.

6. The radio receiving apparatus as recited in claim 1, said radio receiving apparatus being characterized in that said regional level acquirer causes said regional level storage to store differences between a preset reference value and the signal levels acquired in said individual regions as signal levels in said individual regions, and said corrector portion performs said correction by adding the signal levels in said individual regions stored in said regional level storage to the signal levels in said individual regions received by said receiver portion, respectively.

7. The radio receiving apparatus as recited in claim 1, said radio receiving apparatus being characterized in that said receiver portion is provided with:

an antenna portion for receiving said radio signal and outputting the received signal;

a filter portion which can extract at least part of components in a frequency band used by said radio signal with the received signal input into said filter portion;

a detector portion for detecting an envelope or peaks of an output of said filter portion;

an integrator portion for accumulating an output of said detector portion for a specific integration period; and

an analog-to-digital converter for A/D-converting an output voltage of said integrator portion;

wherein said demodulator portion adjusts said integration period of said integrator portion based on values A/D-converted by said analog-to-digital converter; and

said radio receiving apparatus further comprises a gain controller for adjusting for adjusting a frequency passband of said filter portion according to a variance of the values A/D-converted by said analog-to-digital converter.

8. The radio receiving apparatus as recited in claim 7, said radio receiving apparatus being characterized in that said receiver portion is further provided with an amplifier portion connected between said filter portion and said detector portion, wherein gain of said amplifier portion is adjusted by a signal fed from said gain controller.

9. The radio receiving apparatus as recited in claim 7, said radio receiving apparatus being characterized in that said gain controller judges whether any received signal exists from the variance of the values A/D-converted by said analog-to-digital converter and restricts acquisition of the variance during the integration period in which the received signal exists.

10. A radio receiving method for receiving a radio signal having pulsating signals occurring at specific periods, said radio receiving method being characterized by comprising:

a step of receiving said radio signal by a receiver portion;

a step of acquiring a signal level obtained by said receiver portion in each of plural regions into which each of said periods is divided;

a step of storing signal levels acquired in said individual regions under conditions where the radio signal is not received by said receiver portion in a regional level storage for said individual regions;

a step of correcting said received signal levels in said individual regions based on the signal levels stored in said regional level storage, respectively; and

a step of demodulating said radio signal according to said corrected signal levels in the individual regions.