Frequency spectrum analyzer with displayable colored shiftable frequency spectrogram

Claim 2

A frequency spectrum analyzer comprising: a frequency spectrograph for repeatedly analyzing an input signal applied thereto and for separating said input signal into a plurality of different frequency components; coder means for deriving a train of time sequentially aligned digital pulse codes each representing the intensity of one of said separate frequency components, respectively; first time compressor means for grouping said digital pulse codes into groups of a certain number each and for providing time compression within each group between the digital pulse codes so as to form a train of time sequentially aligned pulse code groups; second time compressor means for repeatedly shifting each one of the pulse code groups to a preceding position from its succeeding one in the pulse code groups a limited number of times, respectively, so as to form a train of time compressed pulse code groups; and a visual display device for operatingly providing a visual display in response to said train of shifted pulse pulse code groups, whereby a visual shiftable frequency spectrogram is obtained.

Claim 3

A frequency spectrum analyzer according to claim 1, which further comprises decoder means for operatingly generating a plurality of level representative signals in response to the designations of the respective digital pulse codes; and means for operatively generating color defining signals which define a series of predetermined different colors in response to the level representative signals.

Claim 4

A frequency spectrum analyzer according to claim 2, wherein said visual display device comprises a color picture tube and its associated driving circuit means for operatingly providing a color display in which respective colors correspond to different intensities of the analyzed frequency components of the input signal.

Claim 5

A frequency spectrum analyzer according to claim 3, wherein said frequency spectrograph includes a plurality of band-pass filters connected in parallel to a source of input signals and each having a band-pass forming a respective section of a frequency spectrum and a sequencer for consecutively connecting said band-pass filters to an output terminal.

Claim 6

A frequency spectrum analyzer according to claim 4, wherein said coder means is provided as an analog-to-digital converter connected to the output terminal of said frequency spectrograph.

Claim 7

A frequency spectrum analyzer according to claim 2, wherein said coder means provides a plurality of outputs each supplying a respective digit of said digital pulse codes, and said first time compressor means including first time compressor circuits connected respectively to each output of said coder means.

Claim 8

A frequency spectrum analyzer according to claim 6, wherein said first time compressor circuits each include a first delay line, first gating means selectively connecting an output of said coder means to said delay line, second gating means connecting the output of said delay line to said first gating means, first timing means for actuating said second gating means to effect recirculation of said applied digit through said delay line a predetermined number of times, and third gating means responsive to said timing means for connecting the output of said first gating means to an output terminal after receipt of said certain number number of code pulses.

Claim 9

A frequency spectrum analyzer according to claim 7, wherein said second time compressor means includes second time compressor circuits connected respectively to to the output of each first time compressor circuit.

Claim 10

A frequency spectrum analyzer according to claim 8, wherein said secoNd time compressor circuits each include a second delay line, fourth gating means selectively connecting a respective first time compressor circuit to said second delay line, fifth gating means connecting the output of said second delay line to said fourth gating means, and second timing means responsive to said first timing means for actuating said fifth gating means effect recirculation effect recirculation of said pulse groups delay said second delay line a predetermined number of times.

Claim 11

A frequency spectrum analyzer according to claim 3, wherein said frequency spectrograph includes band-pass filter means sequentially and repeatedly providing an array of different frequency band-pass characteristics each of which relating to a different relatively narrow frequency band and all of which together encompassing a relatively wide frequency band input signal, so that said input signal is repeatedly sampled to thereby obtain as its output a train of time sequentially aligned different frequency components of said input signal, first connecting means for connecting the input signal to be analyzed to said band-pass filter means, and second connecting means for connecting the output of said band-pass filter means to said coder means; said driving circuit means associated with said color picture tube in said visual display device including means for providing coordinate direction scanning in a color display on said color picture tube, the scanning in one of the coordinate directions being in synchronism with the repetition of said array of the band-pass characteristics by said band-pass means, so that said one coordinate direction represents a frequency axis, whereas the scanning in the other one of the coordinate directions having a relatively long time period so as to be representative of a time period axis, and means for supplying the color defining signals to said color picture color thereby operatingly providing different color displays at different positions in said coordinate display on said color picture tube in response to the level representative signals.

Claim 12

A frequency spectrum analyzer according to claim 10, wherein said band-pass filter means includes a bank of filters each of which is a relatively narrow band-pass filter compared to the frequency spectrum width of the input signal to be analyzed, the band-pass frequencies of said filters being arranged in an ordered array, said filters together encompassing the relatively wide frequency band input signal supplied thereto; and scanning means for sequentially sampling the responses of said filters one after another repeatedly and for transfering the sampled output to said second connecting means.