US3818332A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Testing system for measuring the characteristics of a network over a variable frequency range
Assignee: Siemens AG
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Filing: 1973-03-08
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Granted: 1974-06-18
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Expires: 1993-03-08
Abstract
Abstract A testing system for determining the attenuation and phase shift characteristics of a network, wherein a variable frequency signal is applied to the network and simultaneously to a parallel path. The frequency of the signal passing through the test network is shifted to a first frequency range and the signal passing through the parallel network which does not contain the test network is shifted to a second frequency range; and these two signals are then combined and passed via a frequency converter stage to a pair of band pass filters, respectively tuned to pass the shifted and subsequently converted signal which has passed through the test network, and the shifted and subsequently converted signal which has passed through the parallel network. One of the said signals is, after passing the allocated band pass filter, converted to the same frequency as the other signal, this enabling a comparison of these signals with one another, so as to indicate attenuation and phase shifts in the test network.
Inventors
- 👤 K Schlosser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:22
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/46; H04B3/462; H04B3/466; G; G01; G01R; G01R21/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
328 words
A testing and measuring system comprising a test oscillator capable of producing a frequency modulated output signal, an evaluation system for comparing a pair of input signals to produce indications indicative of differences between said input signals, a test object for which the transmission properties are desired, a first signal path including said object connected between said test oscillator and said evaluation system, and a second signal path between said test oscillator and said evaluation system which does not include said test object, said input signals being continuously supplied to said evaluation system through said first and second signal paths, a first modulator in said first signal path for producing a first side frequency signal from said frequency modulated output signal, a second modulator in said second signal path for producing a second side frequency signal from said frequency modulated output signal, and a pair of auxiliary low frequency sources respectively connected to said first and second modulators, a common portion of said first and second signal paths comprising an adder receiving the outputs of said first and second modulators, a frequency converter receiving the output of said adder, said first and second signal paths separating after said frequency converter, a first band pass filter tuned to the converted first side frequency signal and connected between said frequency converter and said evaluation system in said first signal path, a second band pass filter in said second signal path tuned to the converted second side frequency signal and receiving an output of said frequency converter, a second frequency converter connected between one of said band pass filters and said evaluation system in the signal path allocated to that filter, and a mixer supplying an input to said second frequency converter, the output signal of said second frequency converter constituting one of said input signals and the output signal of the band pass filter in the signal path without said second frequency converter constituting the other of said input signals.
Claim 2
Dependent Claim
328 words
A testing and measuring system comprising a test oscillator capable of producing a frequency modulated output signal, an evaluation system for comparing a pair of input signals to produce indications indicative of differences between said input signals, a test object for which the transmission properties are desired, a first signal path including said object connected between said test oscillator and said evaluation system, and a second signal path between said test oscillator and said evaluation system which does not include said test object, said input signals being continuously supplied to said evaluation system through said first and second signal paths, a first modulator in said first signal path for producing a first side frequency signal from said frequency modulated output signal, a second modulator in said second signal path for producing a second side frequency signal from said frequency modulated output signal, and a pair of auxiliary low frequency sources respectively connected to said first and second modulators, a common portion of said first and second signal paths comprising an adder receiving the outputs of said first and second modulators, a frequency converter receiving the output of said adder, said first and second signal paths separating after said frequency converter, a first band pass filter tuned to the converted first side frequency signal and connected between said frequency converter and said evaluation system in said first signal path, a second band pass filter in said second signal path tuned to the converted second side frequency signal and receiving an output of said frequency converter, a second frequency converter connected between one of said band pass filters and said evaluation system in the signal path allocated to that filter, and a mixer supplying an input to said second frequency converter, the output signal of said second frequency converter constituting one of said input signals and the output signal of the band pass filter in the signal path without said second frequency converter constituting the other of said input signals.
Claim 3
Dependent Claim
26 words
A testing and measuring system according to claim 1, wherein said evaluation system produces an indication of the frequency dependent transmission characteristics of said test object.
Claim 4
Dependent Claim
26 words
A testing and measuring circuit according to claim 1, wherein said evaluation system produces an indication of the frequency dependent phase shift of said test object.
Claim 5
Dependent Claim
54 words
A testing and measuring circuit according to claim 1, wherein said pair of auxiliary low frequency sources take the form of a joint auxiliary alternating voltage source and a pair of frequency dividers which receive the output of said joint auxiliary alternating voltage source and supply output to the said first and second modulators.
Claim 6
Dependent Claim
31 words
A testing and measuring circuit according to claim 1, further comprising a mixer receiving inputs from said pair of auxiliary frequency sources and supplying an input to said second frequency converter.
References Cited (Backward Citations)
US1684403A
Cited
US2047782A
Cited
US2622127A
Cited
US2685063A
Cited
US2580803A
Cited
US2760155A
Cited
US2970258A
Cited
US3379975A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-17 | 1977-12-17 | 1978-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-17 | 1981-12-17 | 1982-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-17 | 1985-12-17 | 1986-06-18 | $7700.00 | Window Closed / Lapsed |