Radio signal receiving method and radio signal receiver

• US 7,336,740 B2
• Filed: 03/01/2004
• Issued: 02/26/2008
• Est. Priority Date: 07/17/2003
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Mizugaki, Kenichi, Suzuki, Hideya
• Primary Examiner(s): Fan; Chieh M.
• Assistant Examiner(s): Lee; Siu M
• Application Number:
  US10/788,461
• Publication Number:
  US 20050013392A1
• Time in Patent Office: 1,457 Days
• Field of Search: 375/316, 375/340, 375/343, 375/146, 375/350
• US Class Current: 375/343
• CPC Class Codes: H04B 1/71637 Receiver aspects H04B1/7183 takes precedence
• CPC Class Codes: H04B 1/719 Interference-related aspects
• CPC Class Codes: H04L 25/4902 Pulse width modulation; Pulse position modulation

Abstract

A radio signal receiving method grasps features of a propagation path at the start of communication and generates a template waveform corresponding to the features. A receiver examines a reception waveform of a propagation path condition judgment portion contained in a header portion of a packet, individually generates the template waveform in each communication session and performs correlation detection on the basis of the template waveform generated individually.

Claims

1. A radio signal receiver in a radio communication system for executing communication by transmitting and receiving pulse signals, comprising:

a template generation portion for generating a template; and

a correlation device for calculating correlation between the template generated and a signal received from a transmitter,

wherein said template generation portion generates the template based on a reception waveform of a first signal as a known signal received from said transmitter,

wherein said correlation device determines a correlation between a second signal received from said transmitter and the template and discriminates the second signal based on the correlation result, and

wherein said template generation portion stores the reception waveform of the first signal as a first reference waveform, generates a second reference waveform by converting the first reference waveform and generates the template by synthesizing the first reference waveform and the second reference waveform.

2. A radio signal receiver as defined in claim 1, wherein said radio communication system discriminates whether the transmission signal is set to 0 or 1 from deviation of a transmission timing of a pulse signal from a reference time, and said template generation portion generates the template by synthesizing the first reference waveform and the second reference waveform obtained by inverting a sign of the first reference waveform and delaying the first reference waveform by a time corresponding to deviation of the transmission timing.

3. A radio signal receiver as defined in claim 1, wherein communication with said transmitter is made through a packet, the first signal is contained in a header portion of said packet and the second signal is contained in an information portion of said packet.

4. A radio communication system for performing communication by transmitting and receiving pulse signals, including a transmitter and a receiver,

wherein said transmitter transmits a second signal after transmission of a predetermined first signal used for judging a propagation path condition between said transmitter and said receiver,

wherein said receiver includes a template generation portion for generating a template, and

a correlation device for calculating correlation between the template generated and the second signal received after the first signal, and performing detection,

wherein said template generation portion acquires a reception waveform of the first signal and stores the reception waveform acquired as a first reference waveform, generates a second reference waveform by converting the first reference waveform, and generates the template by synthesizing said first reference waveform and said second reference waveform.

5. A radio communication system as defined in claim 4, wherein the first signal and the second signal are transmitted during one communication session.

6. A radio communication system as defined in claim 4, wherein said radio communication system discriminates whether the transmission signal is set to 0 or 1 from deviation of a transmission timing of a pulse signal from a reference time, and said template generation portion generates the template by synthesizing the first reference waveform and the second reference waveform obtained by inverting a sign of the first reference waveform and delaying the first reference waveform by a time corresponding to deviation of the transmission timing.

7. A signal receiving method in a radio signal communication system for performing communication by transmitting and receiving pulse signals, comprising the steps of:

receiving a first signal;

judging a propagation path condition between a transmitter and a receiver by use of the first signal;

generating a template used for correlation calculation with a reception signal in accordance with the propagation path condition judged; and

performing the correlation calculation between the template and the second signal,

wherein said step of generating the template includes a step of storing the reception waveform of the first signal as a first reference waveform, a step of generating a second reference waveform by changing the first reference waveform, and a step of synthesizing said first reference waveform and said second reference waveform.

8. A signal receiving method as defined in claim 7, wherein said radio communication system discriminates whether the transmission signal is set to 0 or 1 from deviation of a transmission timing of a pulse signal from a reference time, and

wherein said step of generating the second reference waveform includes a step of inverting a signal of the first reference waveform and deviating its position on a time axis corresponding to deviation of the transmission timing.

9. A signal receiving method as defined in claim 7, wherein the first signal and the second signal are contained in the same packet.