QUANTUM NOISE IN LINEAR AMPLIFIERS

Journal Article · Sat Dec 01 04:00:00 EST 1962 · Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D

DOI:https://doi.org/10.1103/PhysRev.128.2407· OSTI ID:4777496

Haus, H A; Mullen, J A

The classical definition of noise figure, based on signalto-noise ratio, is adapted to the case when quantum noise predominant. The noise figure is normalized to uncertainty noise.'' General quantum mechanical equations for linear amplifiers are set up using the condition of linearity and the requirement that the commutator brackets of the pertinent operators are conserved in the amplification. These equations include as special cases the maser, the parametric amplifier, and the parametric up-converter. Using these equations the noise figure of a general amplifier is derived. The minimum value of this noise figure is equal to 2. The significance of the result with regard to a simultaneous phase and amplitude measurement is explored. (auth)

• Research Organization: Massachusetts Inst. of Tech., Cambridge
• NSA Number: NSA-17-003286
• OSTI ID: 4777496
• Journal Information: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D, Journal Name: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D Vol. Vol: 128; ISSN PHRVA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

AMPLIFIERS
BACKGROUND
EFFICIENCY
EQUATIONS
INSTRUMENTS AND INSTRUMENTATION
MASERS
PARAMETRIC AMPLIFIERS
PULSES
SIGNALS