Signal generator

• US 6,836,231 B2
• Filed: 07/01/2003
• Issued: 12/28/2004
• Est. Priority Date: 05/30/2001
• Status: Expired due to Term

• Current Assignee: Radiodetection Limited
• Original Assignee: Radiodetection Limited
• Inventors: Pearson, Richard David
• Primary Examiner(s): Wamsley, Patrick
• Application Number:
  US10/609,674
• Publication Number:
  US 20040070444A1
• Time in Patent Office: 546 Days
• Field of Search: 341/143, 324/76.11, 324/624, 330/10, 323/284, 219/130.51, 702/60, 702/62, 702/64
• US Class Current: 341/143
• CPC Class Codes: G01R 29/085 for detecting presence or location of electric lines or cables fault detection G01R31/50; fault location G01R31/08
• CPC Class Codes: G01R 31/2841 Signal generators

Abstract

A signal generator controls power output on the basis of the output from a Δ-Σ modulator or oscillator. That output may be generated in real time by the modulator or oscillator and fed to a switch control logic unit which controls a power switching stage to output switchably switched power from a power supply to an output, preferably via a filter. Alternatively the output of a Δ-Σ oscillator or modulator may be stored in a switchable memory to be retrieved when needed. A further alternative is to control the power switching stage by a processor with a program which reproduces the control effect of the Δ-Σ oscillator/modulator. Feedback from the output may be used to control the Δ-Σ modulator/oscillator and/or the power supply.

Claims

1. A signal generator comprising:

a memory storing a signal corresponding to the output of a delta-sigma oscillator or generator, the memory being arranged to output a modulated signal

a power supply;

a switching stage connected to the power supply and the memory for controlling the output of a power signal from said power supply on the basis of the modulated signal from the memory; and

an output circuit for acting on the power signal to generate a generator output signal.

2. A signal generator comprising:

a processor storing a program representing the control of a switching stage using the output of a delta-sigma oscillator or generator;

a power supply;

a switching stage connected to the processor for control thereby under the effect of the program, the switching stage being arranged to control the output of a power signal from said power supply; and

an output circuit for acting on the power signal to generate a generator output signal.