line of sight


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line of sight

[′līn əv ′sīt]
(electromagnetism)
The straight line for a transmitting radar antenna in the direction of the beam.
(science and technology)
A straight, unobstructed path or line between two points, as between an observer's eye and a target.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

line of sight, line of collimation

The line extending from an instrument along which distant objects are seen, when viewed with the telescope or other sighting device. Also see sight line.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.

line of sight

An unobstructed path from a transmitting device to the receiver. Users are aware of line of sight when they aim their infrared (IR) remote control directly at the TV. Microwave transmissions between towers at the top of mountains and buildings require unobstructed line of sight. See IR remote control.

Any Radio Frequency
Technically, line of sight refers to radio frequency (RF) transmission in general, including Wi-Fi and cellular. Although walls and other obstructions may attenuate (lessen) or block signals entirely, the receiving device must be in the radiation pattern emitted by the transmitter, which is also considered line of sight. See RF.
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References in periodicals archive ?
Severe losses beyond line of sight. Ultra-High Frequency UHF Mobile communications and TV.
Line of sight encourages employee feedback--both positive and negative that guides the organization in making continuous improvements or initiating major changes.
The lower court did not agree with OPVA's position and found, as did the court in Lara, that "comparable line of sight" did not include viewing angles but referred only to viewing obstructions.
"Racing drivers get a lot of information via displays built into the steering wheel," says Styles, "which is within the their line of sight, yet disappears from view when the wheel turned at a steep angle." The latter keeps the display from distracting the driver when he should be concentrating on more important tasks.
It is housed in an easy-to-position swivel that can be folded up and out of one's line of sight. Comfortable and lightweight, it comes with either a cotton or leather headband and has a Velcro [R] fastener for a custom fit.
The company's specialties include the design and manufacture advanced products and networks used for transmission of voice, data and video using satellite, over-the-horizon microwave, terrestrial line of sight and other wireless communications systems.
Though we imagine that we are able to see everything that takes place in our immediate environment, Kennedy's footage reveals the way that from moment to moment our vision is anchored in and limited by the narrow physical parameters of our bodies, the way our line of sight is narrowly proscribed by the degree of the tilt or slight turn of the head.
When combined with radial-velocity data this was enough to yield an estimate of the orbit's inclination to our line of sight (roughly 60U), which in turn tells the planet's mass: 10 Jupiters, plus or minus 50 percent.
There's catch--visual line of sight does not necessarily equal radio line of sight.
M2 EQUITYBITES-October 14, 2016-NASA to test multiple drones flying beyond line of sight
* Feedback from soldiers points out occasional periods of "longer than normal" time to send messages to one another, This is not a symptom of network overload but most often occurs when longer messages are sent, when satellite line of sight is interrupted, or when periodic platform-level computer "cleanup" is required.
The more sharply you shoot downward from a tree stand, however, the less ability gravity has to bring the arrow back down to your line of sight once it crosses above it.