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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 ...
Examples of pulse shapes: (a) rectangular pulse, (b) cosine squared (raised cosine) pulse, (c) Dirac pulse, (d) sinc pulse, (e) Gaussian pulse. A pulse in signal processing is a rapid, transient change in the amplitude of a signal from a baseline value to a higher or lower value, followed by a rapid return to the baseline value. [1]
The pulse-repetition frequency (PRF) is the number of pulses of a repeating signal in a specific time unit. The term is used within a number of technical disciplines, notably radar. In radar, a radio signal of a particular carrier frequency is turned on and off; the term "frequency" refers to the carrier, while the PRF refers to the number of ...
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.
The two coincide in fact in NRZ transmission; they do not coincide in a 2B1Q transmission, where one pulse takes the time of two bits. For example, in a serial line with a baud rate of 2.5 Gbit/s, a unit interval is 1/(2.5 Gbit/s) = 0.4 ns/baud.
In this example there are 1000 pulses per second (one kilohertz pulse rate) with a gated pulse width of 42 μs. The pulse packet frequency in this example is 27.125 MHz of RF energy. The duty cycle for a pulsed radio frequency is the percent time the RF packet is on, 4.2% for this example ([0.042 ms × 1000 pulses divided by 1000 ms/s] × 100).
Radar transmission frequency spectrum of a cosine pulse profile. Similarly, the use of a cosine pulse profile has an even more marked effect, with the amplitude of the sidelobes practically becoming negligible. The main lobe is again increased in amplitude and the sidelobes correspondingly reduced, giving a significant improvement in performance.
Pick a frequency f, and assume that there is a hypothetical Single Degree of Freedom (SDOF) system with a damped natural frequency of f ; Calculate (by direct time-domain simulation) the maximum instantaneous absolute acceleration experienced by the mass element of your SDOF at any time during (or after) exposure to the shock in question.