Global Information Lookup Global Information

Nonlinear junction detector information


A bumblebee with a transponder acting as a non-linear junction for tracking the animal by way of harmonic radar.

The non-linear junction detector, or an NLJD, is a device that illuminates a small region of space with high-frequency RF energy. Any "non linear junction" in the vicinity—for example, and particularly, the p–n junction—will receive this energy, and because of the asymmetric response of the junction to an electric field, it will mangle it, re-emitting some of it on multiples of the illumination frequency (see harmonic). The detector has a sensitive receiver tuned to these harmonics, as well as appropriate processing and displays to make their presence known to the user of the device. Because the basis of almost all semiconductor electronics is the p-n junction, an NLJD is correspondingly capable of detecting almost any unshielded electronic device containing semiconductors, whether the electronics are actively powered or not.

In its basic form, an NLJD can also detect things that are not themselves electronic in nature, so the use of the device requires a modicum of skill and experience. For example, a rusty nail inside a wall can give a false positive. For this reason, most modern NLJDs examine the ratio between the second and the third harmonic of the illumination frequency. When a true (electronic) p-n junction is encountered, the second harmonic will generally be stronger than the third.

and 25 Related for: Nonlinear junction detector information

Request time (Page generated in 0.8819 seconds.)

Nonlinear junction detector

Last Update:

non-linear junction detector, or an NLJD, is a device that illuminates a small region of space with high-frequency RF energy. Any "non linear junction" in the...

Word Count : 540

Crystal detector

Last Update:

A crystal detector is an obsolete electronic component used in some early 20th century radio receivers that consists of a piece of crystalline mineral...

Word Count : 8404

Photodetector

Last Update:

region. Photodiodes and photo transistors are a few examples of photo detectors. Solar cells convert some of the light energy absorbed into electrical...

Word Count : 2417

Covert listening device

Last Update:

2004-2005 Mobile phone tracking National Cryptologic Museum Nonlinear junction detector Peter Wright Privacy Privacy International Surveillance Technical...

Word Count : 3336

Countersurveillance

Last Update:

general measurements of power supplies and device components. Nonlinear junction detector (NLJD) to detect components associated with hidden eavesdropping...

Word Count : 1812

Husky VMMD

Last Update:

countermeasures Remote weapon station Metal detectors Ground-penetrating radar Nonlinear junction detectors Gunfire detectors Robotic arms Blowers Water diggers...

Word Count : 1024

Position sensitive device

Last Update:

size unlike the quadrant detector which could be easily changed by air turbulence. However, it suffers from the nonlinearity problem. While the position...

Word Count : 1209

Cryogenic particle detector

Last Update:

energy. The STJ can also be used as a heterodyne detector by exploiting the change in the nonlinear current–voltage characteristic that results from photon-assisted...

Word Count : 1451

Superconducting tunnel junction

Last Update:

detectors from the European Space Agency, accessed 8-17-11 Likharev, K.K.; Semenov, V.K. (1991). "RSFQ logic/memory family: a new Josephson-junction technology...

Word Count : 1658

Bipolar junction transistor

Last Update:

A bipolar junction transistor (BJT) is a type of transistor that uses both electrons and electron holes as charge carriers. In contrast, a unipolar transistor...

Word Count : 6795

Coherer

Last Update:

The coherer was a primitive form of radio signal detector used in the first radio receivers during the wireless telegraphy era at the beginning of the...

Word Count : 3064

Amplifier

Last Update:

voltage. AM detector circuits that use amplification such as anode-bend detectors, precision rectifiers and infinite impedance detectors (so excluding...

Word Count : 7058

PIN diode

Last Update:

creating current. Some detectors can use avalanche multiplication. The same mechanism applies to the PIN structure, or p-i-n junction, of a solar cell. In...

Word Count : 2178

Silicon photonics

Last Update:

pure germanium. Most detectors use a PN junction for carrier extraction, however, detectors based on metal–semiconductor junctions (with germanium as the...

Word Count : 6368

Schottky diode

Last Update:

by the junction of a semiconductor with a metal. It has a low forward voltage drop and a very fast switching action. The cat's-whisker detectors used in...

Word Count : 2481

Radio receiver

Last Update:

semiconductor junction functioned as a Schottky barrier diode, conducting in only one direction. Only particular sites on the crystal surface worked as detector junctions...

Word Count : 16580

Memristor

Last Update:

(2.80) Muthuswamy, Bharathwaj; Banerjee, Santo (2019). Introduction to Nonlinear Circuits and Networks. Springer International. ISBN 978-3-319-67325-7...

Word Count : 13866

Regenerative circuit

Last Update:

here, the active device also functions as a detector; this circuit is also known as a regenerative detector. A regeneration control is usually provided...

Word Count : 3600

Gunn diode

Last Update:

e.g., in books on transferred electron devices and, more recently, on nonlinear wave methods for charge transport. The electronic band structure of some...

Word Count : 1747

Ferroelectricity

Last Update:

Some materials, known as paraelectric materials, show a more enhanced nonlinear polarization (see figure). The electric permittivity, corresponding to...

Word Count : 4131

Neon lamp

Last Update:

historically used as microwave and millimeter-wave detectors ("plasma diodes" or glow discharge detectors (GDDs)) up to about 100 GHz or so and in such service...

Word Count : 3012

Varistor

Last Update:

electrical resistance that varies with the applied voltage. It has a nonlinear, non-ohmic current–voltage characteristic that is similar to that of a...

Word Count : 2689

Terahertz radiation

Last Update:

radiation using a semiconductor source. THz radiation was generated by nonlinear mixing of two modes in a mid-infrared quantum cascade laser. Previous...

Word Count : 6782

Marissa Giustina

Last Update:

states. Her quantum computers are based on nonlinear superconducting elements, which comprise a Josephson junction integrated as a non-linear element. This...

Word Count : 719

Electron backscatter diffraction

Last Update:

is carried out in a scanning electron microscope equipped with an EBSD detector comprising at least a phosphorescent screen, a compact lens and a low-light...

Word Count : 13674

PDF Search Engine © AllGlobal.net