Spectrum spread receiver and spectrum spread transmitter-receiver including same

• US 5,479,442 A
• Filed: 08/16/1993
• Issued: 12/26/1995
• Est. Priority Date: 08/31/1992
• Status: Expired due to Fees

• Current Assignee: Futaba Denshi Kogyo KK
• Original Assignee: Futaba Denshi Kogyo KK
• Inventors: Yamamoto, Michio
• Primary Examiner(s): Gregory, Bernarr E.
• Application Number:
  US08/106,653
• Time in Patent Office: 862 Days
• Field of Search: 375/1, 375/200-210, 380/34, 455/336, 329/367, 340/539
• US Class Current: 375/150
• CPC Class Codes: H04B 1/707 using direct sequence modulation

Abstract

A spectrum spreading receiver including a super-regenerative demodulator which is capable of receiving a spectrum spread signal and which is resistant to noise and has a wide band, resulting in being simplified in structure and decreased in manufacturing cost. A signal of which a spectrum is spread by a PN code is received by a receiving antenna and then demodulated by the super-regenerative demodulator. Then the same PN code as the PN code having carried out the spectrum spreading is generated and the correlation between the signal and the PN code is made by a correlation unit, resulting in the decoding of the spread signal into the original base band signal.

Claims

1. A spectrum spread receiver comprising:

a means for receiving a spectrum spread transmitted signal;

a super-regenerative demodulator for demodulating the received signal, to thereby produce a spectrum spread signal; and

a correlation unit for multiplying the spectrum spread signal by a PN code to decode the signal, to thereby produce the original base band signal; and

a decoder receiving as an input the signal decoded in said correlation unit, wherein said decoder separates the decoded signal into a plurality of channel signals and said decoder provides error checking.

2. A spectrum spreading receiver as defined in claim 1 wherein said decoder carries out detection of coincidence of said signal with an identification code.

3. A spectrum spreading transceiver comprising:

a spectrum spreading transmitter for transmitting a carrier signal including an encoder for multiplexing a plurality of signals to produce a multiplexed signal,

a modulator for modulating said carrier signal and

an exclusive OR circuit for subjecting the multiplexed signal and a PN code fed thereto to spectrum spreading, in order to produce a spectrum spread signal for modulating said carrier signal to be transmitted; and

a spectrum spreading receiver including a means for receiving the spectrum spread signal, a super-regenerative demodulator for demodulating the received signal, a correlation unit for multiplying the spectrum spread signal by a PN code to decode the signal, and a decoder for separating the decoded signal into a plurality of channel signals.

4. The spectrum spreading transceiver as defined in claim 3, wherein said encoder carries out addition of an identification code and said decoder detects coincidence of said signal with the identification code.

5. A spectrum spreading transceiver as defined in claim 3 or 4, wherein said decoder carries out error checking.

6. A spectrum spreading receiver, comprising:

a receiving antenna for receiving a radio wave signal which has been spectrum spread and modulated in a transmitter;

a super regenerative modulator including radio-frequency and quenching oscillators for demodulating the signals received by said receiving antenna; and

a reverse spreading circuit which includes a correlation unit and a pseudo-noise code generator for decoding the signals output by said super regenerative demodulator so as to produce the radio wave signal prior to spectrum spreading;

a waveform shaper for converting the spectrum spread signal into a pulse waveform;

a decoder for identifying the signal output by said reverse spreading circuit; and

an error checking circuit for checking the signal output by said reverse spreading circuit for errors.