direct wave

direct wave

[də¦rekt ′wāv]
(communications)
A radio wave that is propagated directly through space from transmitter to receiver without being refracted by the ionosphere.

direct wave

direct wave
Direct and indirect waves.
An electromagnetic wave that travels directly from a transmitting antenna to the receiving antenna along a straight line. Direct waves are responsible for part, but not all, of the signal propagation between two antennae when a sight line connecting the antennae lies above the ground. The surface (ground) wave and the reflected wave also contribute to the overall signal at the receiving antenna. Also called a line-of-sight wave or a space wave, it is prevalent in frequencies above 30 MHz.
References in periodicals archive ?
When delay time is being estimated, the time of arrival (TOA) of a direct wave from the broadcasting station is employed as the reference.
These spans can be susceptible to failure through fatigue and, as span length increases, the risk of fatigue damage due to direct wave loading or vortex-induced vibrations (VIV) also increases.
The distortion of signals because of the arrival time differences of the direct wave and the reflected wave decreases DF accuracy.
Alternatively, the company has relied on the direct wave receiver that vibrates the entire handset to produce sound.
Obviously, (for case A1) the direct wave arrives at the AOA estimator at the angle 170[degrees], as in Fig.
Washington, Mar 14 ( ANI ): Scientists have for the first time identified direct wave motion in one of Jupiter's jet streams.
developer of direct wave energy conversion device, today announced the appointment of Mr.
Some areas covered include ray-based tomography imaging methods, hybrid ray-wave imaging approaches, direct wave equation imaging of the Earth's interior, modeling wave propagation in complex structures, and numerical means of describing complicated Earth structures.
direct wave, ground-roll forming a shadow cone and a primary reflection between 1.
To better understand the ionic and electrical effects of trapped flux residue, we used B-24 test coupons processed with selective pallet areas and direct wave solder areas processed on the customer's production line with the low VOC no-clean flux.
For many wireless applications in the 50 to 2000 MHz range, such as broadcasting, paging and mobile telephony, two components of the space wave are of primary concern: energy received by means of the direct wave, which travels a direct path from the transmitter to the receiver, and the ground-reflected wave, which arrives at the receiver after being reflected from the surface of the earth.
When an interferometer antenna array is mounted on any type of mast, ground vehicle or aircraft, the signal received by each antenna will be a combination of the direct wave from the target transmitter and reflections of that wave from everything near the array.