Signal analyzers and frequency domain data production methods
Sets of time domain data of respective frequency bands from Fd- 1 to Fd-n of a periodic input signal Fs are acquired. Sets of the time domain data of the common frequency band are extracted from the sets of the time domain data of the frequency bands Fd- 1 and Fd- 2 in the acquired frequency bands. Correlativity between the sets of the time domain data of the common frequency band is determined while shifting time relationship between the sets each other to identify the sets of time domain data having correspondence relationship. The sets of the time domain data having the correspondence relationship in the time domain data of the adjacent frequency band Fd- 1 and Fd- 2 are converted to the sets of the frequency domain data respectively, and the sets of the frequency domain data are combined to produce one set of combined frequency domain data.
1. A signal analyzer comprising:
data acquisition means receiving an input signal having periodicity for acquiring sets of time domain data of respective frequency bands of the input signal wherein the frequency bands have common frequency bands in adjacent portions; and
calculation means extracting sets of time domain data of the common frequency bands of the adjacent frequency bands in the acquired time domain data of the frequency bands, identifying the corresponding sets of the time domain data of the adjacent frequency bands using the extracted sets of the time domain data of the common frequency bands and converting the corresponding sets of the time domain data into respective sets of frequency domain data to combine them;
wherein if the number of the corresponding sets of the time domain data of the adjacent frequency bands is less than a predetermined number, the data acquisition means acquires one of or both the sets of the time domain data of the adjacent frequency bands again.