Transceiver providing selectable frequencies and spreading sequences

• US 5,357,541 A
• Filed: 04/29/1993
• Issued: 10/18/1994
• Est. Priority Date: 03/23/1989
• Status: Expired due to Term

• Current Assignee: Echelon Corporation (Renesas Electronics Corporation)
• Original Assignee: Echelon Corporation (Renesas Electronics Corporation)
• Inventors: Cowart, Brooks E.
• Primary Examiner(s): Cain, David C.
• Application Number:
  US08/020,589
• Time in Patent Office: 537 Days
• Field of Search: 375/1, 380/34
• US Class Current: 375/141
• CPC Class Codes: H04B 1/7075 with code phase acquisition
• CPC Class Codes: H04B 1/70755 Setting of lock conditions, e.g. threshold
• CPC Class Codes: H04B 1/70757 with increased resolution, i.e. higher than half a chip H04B1/70758 takes precedence
• CPC Class Codes: H04B 1/708 Parallel implementation
• CPC Class Codes: H04B 2201/70703 using multiple or variable rates

Abstract

A transceiver for transmitting and receiving digital data is disclosed. The transceiver employs direct sequence spread spectrum communications techniques for reducing interference among multiple users in a communications network environment. Each transceiver has a transmitter for locking a digital bit stream to a predetermined spread spectrum chip sequence and carrier signal. Frequency of the carrier signal and the chip sequence. Both the carrier signal, the chip sequence and the bit stream rate are derived from an integrally related to an accurate reference frequency to facilitate rapid acquisition and decoding of the signal by another transceiver. To provide for multiple communications channels on a single transmission medium, means for producing selectable carrier frequencies and/or selectable spreading sequences are included. The transceiver also has a receiver portion for acquiring and decoding a transmitted and direct sequence spread spectrum signal to recover the digital bit stream using the spread spectrum chip sequence and carrier signal.

Claims

1. An integrated circuit for transmitting and receiving digital information across various communications media comprising:

a generator for generating a reference frequency;

a transmitter for modulating a predetermined spread spectrum signal with a digital bit stream using binary phase shift keying for transmission to another integrated circuit under control of said reference frequency;

a receiver for acquiring and decoding with a local predetermined sequence, a previously transmitted spread spectrum signal modulated using binary phase shift keying to recover said digital bit stream; and

wherein said predetermined spread spectrum signal has a fixed relationship to said local predetermined sequence and each of said predetermined spread spectrum signal and said local predetermined sequence has a fixed relationship to said reference frequency.