Since emissions from a point source have radial directions, they intercept at a perpendicular incidence.

In telecommunications, a third-order intercept point ( IP < sub > 3 </ sub > or TOI ) is a measure for weakly nonlinear systems and devices, for example receivers, linear amplifiers and mixers.

The third-order intercept point relates nonlinear products caused by the third-order nonlinear term to the linearly amplified signal, in contrast to the second-order intercept point that uses second order terms.

The intercept point is obtained graphically by plotting the output power versus the input power both on logarithmic scales ( e. g., decibels ).

Both curves are extended with straight lines of slope 1 and n ( 3 for a third-order intercept point ).

The point where the curves intersect is the intercept point.

It can be read off from the input or output power axis, leading to input or output intercept point, respectively ( IIP3 / OIP3 ).

Input and output intercept point differ by the small-signal gain of the device.

The concept of intercept point is based on the assumption of a weakly nonlinear system, meaning that higher-order nonlinear terms are small enough to be negligible.

The intercept point according to its basic definition should be determined by drawing the straight lines with slope 1 and n through the measured data at the smallest possible power level ( possibly limited towards lower power levels by instrument or device noise ).

In certain situations such a measure can be useful, but it is not an intercept point according to definition.

One of the useful applications of third order intercept point is as a rule-of-thumb measure to estimate nonlinear products.

For example, assume a device with an input-referred third-order intercept point of 10 dBm is driven with a test signal of − 5 dBm.

This power is 15 dB below the intercept point, therefore nonlinear products will appear at approximately 2x15 dB below the test signal power at the device output ( in other words, 3 × 15 dB below the output-referred third-order intercept point ).

A rule-of-thumb that holds for many linear radio frequency amplifiers is that the 1 dB compression point falls approximately 10 dB below the third-order intercept point.

The third-order intercept point ( TOI ) is a property of the device transfer function O ( see diagram ).

This reduces to the relationship: Af, where Af is the intercept at zero thickness of the extrapolation of the slope indicated in eqn. ( 1 ), Af is the thickness of the coating equivalent to the rounding off of the knife tip, Af is a straight line first approximation of this roundness, and the other symbols are equivalent to those of eqn. ( 1 ).

* their canopies intercept a proportion of precipitation, which is then evaporated back to the atmosphere ( canopy interception );

A comprehensive worldwide surveillance network is possible only if clandestine intercept sites are installed in the territory of friendly nations, and / or if local authorities cooperate.

This relationship is represented in a linear regression where the change in unemployment rate () is a function of an intercept (), a given value of GNP growth multiplied by a slope coefficient and an error term,:

The intercept may also be biased if there is a logarithmic transformation.

An interceptor is generally an aircraft intended to target ( or intercept ) bombers and so often trades maneuverability for climb rate.

Israel deployed a national ABM system based on the Arrow missile in 1998, but it is mainly designed to intercept shorter-ranged theater ballistic missiles, not ICBMs.

The graph of the equation has x-intercept a and y-intercept b. The intercept form is in standard form with A =

The age is calculated from the slope of the isochron ( line ) and the original composition from the intercept of the isochron with the y-axis.

* Telnet, by default, does not encrypt any data sent over the connection ( including passwords ), and so it is often practical to eavesdrop on the communications and use the password later for malicious purposes ; anybody who has access to a router, switch, hub or gateway located on the network between the two hosts where Telnet is being used can intercept the packets passing by and obtain login, password and whatever else is typed with a packet analyzer.

The more times the offense is forced to throw the greater the chance that the handlers will make a bad throw, or a defender will intercept the disc.

This is popular with the military and spies, who both wish to minimize the chance of their radio transmissions being detected, i. e. Low probability of intercept ( LPI ) and Low probability of recognition ( LPR ).

In signal processing, phase distortion or phase-frequency distortion is distortion that occurs when ( a ) a filter's phase response is not linear over the frequency range of interest, that is, the phase shift introduced by a circuit or device is not directly proportional to frequency, or ( b ) the zero-frequency intercept of the phase-frequency characteristic is not 0 or an integral multiple of 2π radians.

Here is the power density of the incident radiation, and is the antenna aperture or effective area of the antenna ( the area the antenna would need to occupy in order to intercept the observed captured power ).

A shield is a type of personal armor, meant to intercept attacks, either by stopping projectiles such as arrows or redirecting a hit from a sword, mace or battle axe to the side of the shield-bearer.

* The concept of intercept point has no meaning for strongly nonlinear systems, such as when an output signal is clipped due to limited supply voltage.

An example illustrating the concept behind the intercept method for determining one ’ s position is shown to the right.

( The intercept method uses the concept illustrated in the example in the “ How it works ” section above.

Tools such as strace and truss allow a process to execute from start and report all system calls the process invokes, or can attach to an already running process and intercept any system call made by said process if the operation does not violate the permissions of the user.

Also present are another military officer whom the passenger had said would take over the country with tyranny if his superior died ( and whose uniform matches the soldiers who had tried to intercept the heart ), and US agents who ensure that he does not interfere with the surgery, and so is forced to give up his attempt to take the country by force.

Missile Defense does not station weapons in space, but is designed to intercept incoming warheads at a very high altitude which requires the interceptor to travel into space to achieve the intercept.

Here, the man-in-the-middle attack does not necessarily require the control of gateway since an attacker that resides on the same Local Area Network ( LAN ), can use an Address Resolution Protocol ( ARP ) spoofing tool such as " ettercap " to intercept or modify all the email packets going to and from the mail server or gateway.

Her purpose is to prevent a similar battle from occurring between the Tokyo-ship and another ship, each soon to intercept the other.

However someone with physical access to the machine may still be able to install software that is able to intercept this information elsewhere in the operating system or while in transit on the network.

It is a frequent mistake to derive intercept points by either changing the slope of the straight lines, or fitting them to points measured at too high a power level.

The larger an antenna, the more power it can intercept.

Two of these were intercept tests in early 1995 ; both failed to intercept — the first had a software error in the second stage booster, the second had a squib ( pyrotechnic switch to connect power ) in the kinetic kill vehicle that was mounted backwards and failed to fire.

The power threshold in each case is given by the intercept of the slope with the x-axis.

Its replacement the Security Offences ( Special Measures ) Act 2012 no longer allows for detention without trial but provides the police, in relation to security offences, with a number of special investigative and other powers such as the power to arrest suspects for an extended period of 28 days ( section 4 of the Act ), intercept communications ( section 6 ), and monitor suspects using electronic monitoring devices ( section 7 ).

More precisely, the RCS of a radar target is the hypothetical area required to intercept the transmitted power density at the target such that if the total intercepted power were re-radiated isotropically, the power density actually observed at the receiver is produced.

As Vice-President, she assumes command of the military in President Parker's absence, as indeed the law states that when the President is indisposed all power is vested in the Vice-President, when an invasion is launched against the United States and orders the military to intercept the invaders who turn back.

The aperture is defined as the area, oriented perpendicular to the direction of an incoming radio wave, which would intercept the same amount of power from that wave as is produced by the antenna receiving it.

The former created the power to intercept communications without adequate safeguards against abuse.

On the other hand, inappropriate inclusion of the intercept or time trend term reduces the power of the unit root test, and sometimes that reduced power can be substantial.