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Typically, these fences are 2.4 metres (7 ft 10 in) tall and send high voltage electric pulses through the palisade at a frequency of 1 Hz (one pulse per second). Palisade electric fences are used in most countries, particularly where there is little vegetation to short-circuit the fence or where the costs of security personnel are high in ...
Invisible Fence Inc. (commonly referred to as Invisible Fence Brand) is a company that designs radio pet fences for cats and dogs. Manufactured and distributed by Radio System Corporation, the company sells wireless and fenceless systems that were first introduced in 1973. [ 1 ]
Cover pulse jamming creates a short noise pulse when radar signal is received thus concealing any aircraft flying behind the jammer with a block of noise. Digital radio frequency memory , or DRFM jamming , or Repeater jamming is a repeater technique that manipulates received radar energy and retransmits it to change the return the radar sees.
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Active signal is issued when both lines present 0 V; a single line presenting 0 V for a duration longer than the test pulses is sufficient to signal an event. Some related terms: Electrosensitive protective equipment (ESPE) - a device such as a light curtain, safety scanner, or gate position sensor. The ESPE has OSSD outputs.
The spectral shear is typically generated by sum-frequency mixing the test pulse with two different quasi-monochromatic frequencies (usually derived by chirping a copy of the pulse itself), although it can also be achieved by spectral filtering or even with linear electro-optic modulators for picosecond pulses.
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FROG extends this idea by measuring the spectrum of the signal at each delay (hence “frequency-resolved”), instead of just the intensity. This measurement creates a spectrogram of the pulse, which can be used to determine the complex electric field as a function of time or frequency as long as the nonlinearity of the medium is known.