Showing papers on "L band published in 1981"
TL;DR: In this article, an adequate spectroscopic data base for air consists of three terms: (1) resonance information for 29 H2O lines up to 1097 GHz and 44 O2 line up to 834 GHz in the form of intensity coefficients and center frequency for each line; (2) an empirical water vapor continuum spectrum; and (3) a liquid water attenuation term for haze and cloud conditions.
Abstract: Moist air is characterized for the frequency range 1–1000 GHz as a nonturbulent propagation medium described by meteorological parameters An adequate spectroscopic data base for air consists of three terms: (1) resonance information for 29 H2O lines up to 1097 GHz and 44 O2 lines up to 834 GHz in the form of intensity coefficients and center frequency for each line; (2) an empirical water vapor continuum spectrum; and (3) a liquid water attenuation term for haze and cloud conditions This data base is the heart of two computer programs which calculate and plot attenuation rates (in decibels per kilometer), refractivity (in parts per million), and refractive dispersion (in parts per million) The first covers the troposphere and requires pressure, temperature, and relative humidity as input data The second addresses isolated line behavior in the mesosphere wherein the geomagnetic field strength H is an additional input parameter due to the Zeeman effect of the O2 molecules Each oxygen line splits proportionally with H into numerous sublines, which are juxtaposed to form Zeeman patterns spread over a megahertz scale Patterns of three main polarization cases are considered Various typical examples for a model atmosphere demonstrate the utility of the approach, provide new information, and underline the serious role that water vapor plays above 120 GHz
138 citations
TL;DR: In this article, a guided optical wave-SAW Bragg cell is reported on Ti-difiused LiNbO3 substrates with a 1.74 GHz center frequency.
Abstract: A 530 MHz bandwidth, 1.74 GHz centre frequency, guided optical wave-SAW Bragg cell is reported on Ti-difiused LiNbO3 substrates.
3 citations
TL;DR: The paper describes how satellite systems are being developed in Canada under these new Regulations and how the 12-GHz band will be used in Region 2.
Abstract: WARC-79 made significant changes to how the 12-GHz band will be used in Region 2. In particular, it decided that the 12-GHz band in Region 2 will extend upwards the 12.7 GHz, and that the upper portion of the overall band (11.7 to 12.7 GHz), will be planned at the 1983 Regional Conference. The paper describes these allocation changes and how satellite systems are being developed in Canada under these new Regulations.
3 citations