Noise spectra of read diode and Gunn oscillators

Josenhans, J.G.

doi:10.1109/proc.1966.5157

Cited by 57 publications

(1 citation statement)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(N/C)HsB = {kTB/P o )/[(S/2)2+(Qextfm/fo)2J, where k is Boltzmann's constant, T is the effective temperature of the device, B is the bandwidth, Po ;s the device output power, S is the saturation factor given by Edson [6], and Q . t is the external circuit quality factor.…”

mentioning

confidence: 99%

Optimal Design Criteria for Millimeter-Wave Spectrometers

Leskovar

Hopkins

Kolbe

1975

1975 5th European Microwave Conference

View full text Add to dashboard Cite

-Optimal design criteria for millimeter-wave cavity-type spectrometeri, used in the measurement of molecular spectra, have been derived. Using an optimally designed spectrometer, the technique of molecular spectroscopy offers a highly sensitive and specific experimental research method for studying chemical kinetics and for monitoring gaseous pollutants and constituents of interest in pollution research. The method is also suitable for the study of the molecular properties of short-lived transient chemical species with lifetimes as short as one millisecond or less. Since the sensitivity of the spectrometer is determined by the total noise introduced during the prbcesses of microwave generation, absorption in the resonant cavity, and the detection and amplification of a spectral line signal. the spectrometer has been analyzed and optimized in detail with respect to the equivalent noise temperatures associated with these processes. The conclusions drawn from the optimum design criteria are applied in the design of a tunable high-Q resonant cavity spectrometer operating at 70 GHz.1. INTRODUCTION -Mi 11 imeter-wave rotati ona 1 spectroscopy measures the absorption in the millimeter region of the electromagnetic spectrum, caused primarily by transitions between pure rotational states of gaseous molecules possessing permanent dipole moments. The physical process leading to absorption is a coupling of the electrical vector of the incident microwave radiation with the permanent dipole moment of the rotating molecule. Using an optimally designed measuring s~stem, this technique is a highly specific and sensitive experimental research method for studying chemica 1 :klf:netit:s and for moni tori ng gaseous poll utants and constituents of interest in pollution research. Our investigations show that in addition to the detection and measurement of ordinary gases and vapors, the method is suitable' for the study of the molecular properties of shortlived transient chemical species with lifetimes down to a millisecond or. less. The technique supplements and may replace gas chromatography, mass spectroscopy, and various laser methods in the identification of trace-gas chemicals, and also makes possible fast, highly specific and sensitive measurements in the laboratory.

show abstract

mentioning

confidence: 99%

Optimal Design Criteria for Millimeter-Wave Spectrometers

Leskovar

Hopkins

Kolbe

1975

1975 5th European Microwave Conference

View full text Add to dashboard Cite

show abstract

Low-Noise, Integrated, Millimeter-Wave Receiver

Glance¹,

Snell²

1974

Bell System Technical Journal

View full text Add to dashboard Cite

A low‐noise, hybrid‐integrated, millimeter‐wave receiver that consists of a local oscillator and a downconverter on a silica substrate is described in this paper. The source for the local oscillator is a Gunn diode, and the mixer element is a beam‐leaded Schottky barrier diode. A novel filter circuit is used to combine the local oscillator and the signal with low insertion loss in the signal path. The single‐sideband noise figure of the receiver at 30 GHz is 5.5 dB, including 0.8‐dB contribution of the if amplifier, and the rms FM frequency variation resulting from the local oscillator is 168 .

show abstract