Patent ID: 6233529
Filing Date: 2001-05-15
Classification: G01R

Abstract:
A spectrum analyzer having a sweep local oscillator for analyzing frequency spectrum of an input signal, comprising:a continuous period measurement block for continuously measuring each time period of an IF (intermediate frequency) signal produced by mixing the input signal and the local oscillator signal; andmeans for processing the data representing the continuous time period produced by the continuous period measurement block to analyze the input signal in a time domain;wherein the continuous period measurement block comprising:a divider for dividing a frequency of the IF signal by a predetermined ratio;a fractional time measurement circuit for measuring a time length of fractional time produced between an edge of the IF signal and a reference clock pulse by expanding the fractional time;a fractional time controller for controlling an operation of measuring the fractional time by the fractional time measurement circuit;a counter for counting the number of reference clock pulse during the time period of the IF signal including the fractional time expanded by the fractional time measurement circuit;a memory for storing data showing the time period obtained by the counter; andan address counter for generating address data for the memory.