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The minimal F wave latency is typically 25-32 ms in the upper extremities and 45-56 ms in the lower extremities. F wave persistence is the number of F waves obtained per the number of stimulations, which is normally 80-100% (or above 50%).
The F-wave latency can be used to derive the conduction velocity of the nerve between the limb and spine. In contrast, the motor and sensory nerve conduction studies evaluate conduction in the segment of the limb. F waves vary in latency and an abnormal variance is called "chrono dispersion".
The waveguide F band is the range of radio frequencies from 90 GHz to 140 GHz in the electromagnetic spectrum, [1] [2] corresponding to the recommended frequency band of operation of WR8 waveguides. These frequencies are equivalent to wave lengths between 3.33 mm and 2.14 mm. The E band is in the EHF range of the radio spectrum.
One of the difficulties posed when broadcasting in the ELF frequency range is antenna size, because the length of the antenna must be at least a substantial fraction of the length of the waves. For example, a 3 Hz signal has a wavelength equal to the distance electromagnetic waves travel through a given medium in one third of a second.
2182 kHz is a medium-wave frequency still used for marine emergency communication. Marine VHF radio is used in coastal waters and relatively short-range communication between vessels and to shore stations. Radios are channelized, with different channels used for different purposes; marine Channel 16 is used for calling and emergencies.
Radio propagation is the behavior of radio waves as they travel, or are propagated, from one point to another in vacuum, or into various parts of the atmosphere. [1]: 26‑1 As a form of electromagnetic radiation, like light waves, radio waves are affected by the phenomena of reflection, refraction, diffraction, absorption, polarization, and scattering. [2]
Propagation delay is equal to d / s where d is the distance and s is the wave propagation speed. In wireless communication, s=c, i.e. the speed of light. In copper wire, the speed s generally ranges from .59c to .77c. [3] [4] This delay is the major obstacle in the development of high-speed computers and is called the interconnect bottleneck in ...
The group delay and phase delay properties of a linear time-invariant (LTI) system are functions of frequency, giving the time from when a frequency component of a time varying physical quantity—for example a voltage signal—appears at the LTI system input, to the time when a copy of that same frequency component—perhaps of a different physical phenomenon—appears at the LTI system output.