Patent ID: 7502980
Filing Date: 2009-03-10
Classification: G01R,H04B,H04L,Y10T

Abstract:
1. A signal generator for generating an output signal corresponding to pattern data, the signal generator comprising: a plurality of timing generators that, based on a reference clock, generate a plurality of periodic signals each having a different phase with respect to the reference clock; a shift register section including a plurality of flip-flops in a cascade arrangement through which each piece of data of the pattern data is propagated sequentially in response to a first periodic signal output from a first timing generator, the first periodic signal being one of the plurality of periodic signals and the first timing generator being one of the plurality of timing generators; a plurality of registers that are provided in a cascade arrangement and in a one-to-one correspondence with the plurality of timing generators excluding the first timing generator, each of the plurality of registers sequentially propagating data output from a pre-selected one of the plurality of flip-flops in response to a periodic signal output from a corresponding one of the plurality of timing generators; and a waveform generating section that generates a waveform of the output signal by multiplying a signal output from said plurality of flip-flops by a first predetermined coefficient, multiplying a signal output from said plurality of registers by a second predetermined coefficient, and adding together waveforms of the multiplied signals.