EP0314301B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Apparatus and method for measuring the signal-to-noise ratio
Assignee: HP Inc
•
Filing: 1988-09-23
•
Granted: 1995-03-08
•
Expires: 2008-09-23
Abstract
No abstract record available.
Inventors
- 👤 Thomas R. Faulkner
- 👤 Earl C. Herleikson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 17:33
CPC Classifications
G; G01; G01R; G01R29/00; G01R29/26
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
175 words
Apparatus for setting the signal-to-noise ratio of a carrier wave (31) having sideband noise components (33) and having a predetermined power level, said apparatus comprising: a signal generator (11) for generating said carrier wave (31) having said sideband noise components (33), attenuation means (13) coupled to said signal generator (11) for attenuating said carrier wave (31) and said sideband noise components (33), said attenuation means (13) having a predetermined attenuation factor, said apparatus further comprising amplifying means (15), coupled to an output of said attenuation means (13) for amplifying a composite signal comprising said attenuated carrier wave and said attenuated sideband noise components (33), characterised in that a noise figure meter (21) is provided for measuring the noise figure of said amplifying means (15); in that said attenuation means (13) has a known thermal noise floor level (35); and in that said predetermined attenuation factor is such that said sideband noise components (33) are attenuated substantially below said thermal noise floor level (35), said amplifying means (15) also amplifying said thermal noise floor level (35).
Claim 2
Dependent Claim
31 words
Apparatus as claimed in claim 1, characterised by power measuring means (19) coupled to the output of said signal generator (11) for measuring the power level of said carrier wave (31).
Claim 3
Dependent Claim
31 words
Apparatus as claimed in claim 1, characterised by power measuring means (19) coupled to the cutput of said attenuation means (13) for measuring the power level of said attenuated carrier wave.
Claim 4
Independent Claim
173 words
A method for setting, at a particular temperature, the signal-to-noise ratio of a carrier wave (31) having sideband noise components (33), said method comprising the steps of: attenuating said carrier wave (31) such that the sideband noise components (33) are attenuated substantially below the thermal noise floor level (35) of an attenuator (13), said attenuator (13) having a predetermined attenuation factor; amplifying said attenuated carrier wave in an amplifier (15) having a known noise figure, said attenuated carrier wave having a known power level and said attenuated sideband noise components (33) being at a level below said thermal noise floor level (35), said thermal noise floor level thereby determining the signal-to-noise ratio of said carrier wave at the output of said amplifier means, as a function of said power level; and adjusting the power level of said carrier wave to provide said carrier wave with a desired signal-to-noise ratio at the output of said amplifier thereby setting said desired signal-to-noise ratio of said carrier wave at said amplifier output at the particular temperature.
Claim 5
Dependent Claim
27 words
A method as claimed in claim 4 further comprising the step of measuring said attenuated carrier wave power level at the input (14) to said amplifier (15).
Claim 6
Dependent Claim
26 words
A method as claimed in claim 4 further comprising the step of measuring said carrier wave (31) power level at the input to said attenuator (13).
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.