Information transmission system
First Claim
1. An information transmission system for sending information along a beam of radiation of a selected wavelength comprising:
- a radiation transmitter and a radiation receiver, the information transmission system sending the information from the radiation transmitter to the radiation receiver, the radiation intensity at the radiation receiver falling as a function of time elapsed from a start of information transmission, the radiation receiver including a radiation detector whose detectivity rises as a function of falling detector temperature and cooling means for progressively reducing the detector temperature from the start of transmission, the detector having a peak in detectivity as a function of wavelength, which peak increases in wavelength from less than the selected wavelength up to at least the selected wavelength as the detector temperature falls towards its operating value.
2 Assignments
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Accused Products
Abstract
An information transmission system is provided for a guided missile 1 in which guidance information is transmitted from the missile launch point to the missile along a beam 8 of 10 μm wavelength radiation. The missile has a rearwards facing optical system 9 to collect and focus the radiation onto a cooled cadmium mercury telluride detector. The proportion of cadmium to mercury in the detector is chosen so that just after launch in the early stage of detector cool-down the long wavelength cut-off of the detector just includes the 10 μm radiation, providing an early guidance signal, and so that, as cooling proceeds, the long wavelength cut-off moves to longer wavelengths thereby rapidly enhancing the received signal to compensate for loss of received energy at the missile due to missile range increase.
10 Citations
6 Claims
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1. An information transmission system for sending information along a beam of radiation of a selected wavelength comprising:
- a radiation transmitter and a radiation receiver, the information transmission system sending the information from the radiation transmitter to the radiation receiver, the radiation intensity at the radiation receiver falling as a function of time elapsed from a start of information transmission, the radiation receiver including a radiation detector whose detectivity rises as a function of falling detector temperature and cooling means for progressively reducing the detector temperature from the start of transmission, the detector having a peak in detectivity as a function of wavelength, which peak increases in wavelength from less than the selected wavelength up to at least the selected wavelength as the detector temperature falls towards its operating value.
- View Dependent Claims (2, 3, 4, 5, 6)
Specification