Radar Tester Interview Preparation Guide

G/T is referred as figure of merit of the RF antenna. G stands for Antenna gain and T stands for Antenna noise temperature. This is most often asked in the interview for satellite group position.

High frequency sound waves are very directional, and they will travel through a medium (like a piece of steel or plastic) until they encounter a boundary with another medium (like air), at which point they reflect back to their source. By analyzing these reflections it is possible to measure the thickness of a test piece, or find evidence of cracks or other hidden internal flaws.

Important parameters relating to vibration pickups/vibrometers are described below: (1) Vibration frequency Unit: Hz (Hertz) Symbol: f Refers to the number of times a vibrating object vibrates per second. The inverse of a vibration frequency is referred to as the period (T), T=1/f.

Vibration analysis can help diagnose many issues ranging from improper lubrication to electrical defects. Some of the most common issues found are: Roller bearing defects, Equipment imbalance, Coupling misalignment, Looseness, Resonance, Gear defects, etc.

GPR is extremely accurate when it comes to locating metallic and non-metallic objects. GPR systems work by sending a tiny pulse of energy into the ground from an antenna. An integrated computer records the strength and time required for the return of reflected signals. Any subsurface variations, metallic or non-metallic, will cause signals to bounce back. When this occurs, all detected items are revealed on the computer screen in real-time as the GPR equipment moves along. Users can even tell from the signal returned whether the feature in question is metallic or non-metallic.

Yes. GSSI’s systems can integrate with most GPS systems. The GPS position data files and GPR scans are automatically matched within our systems so that the resulting data shows proper GPS position.

Some interviewers like to see your reactions to whacky questions like, “If an elephant walked into this room, what would it say?” There is no right/ wrong answer to this one. The interviewer is looking for quick thinking, an ability to handle unprepared situations, a calm demeanour and even a sense of humour. Don’t go overboard on the humour or sarcasm though. Avoid statements that convey negativity or desperation.

The term Wavelength is basically distance from wavecrest to wavecrest along direction of travel of EM wave. The unit is centimeter.

Bistatic radar has two antennas; one for transmission and the other for reception. These antennas either located side by side or they are located far away.

Given below are 6 major parts of a RADAR System:

☛ A Transmitter: It can be a power amplifier like a Klystron, Travelling Wave Tube or a power Oscillator like a Magnetron. The signal is first generated using a waveform generator and then amplified in the power amplifier.
☛ Waveguides: The waveguides are transmission lines for transmission of the RADAR signals.
☛ Antenna: The antenna used can be a parabolic reflector, planar arrays or electronically steered phased arrays.
☛ Duplexer: A duplexer allows the antenna to be used as a transmitter or a receiver. It can be a gaseous device that would produce a short circuit at the input to the receiver when transmitter is working.
☛ Receiver: It can be super heterodyne receiver or any other receiver which consists of a processor to process the signal and detect it.
☛ Threshold Decision: The output of the receiver is compared with a threshold to detect the presence of any object. If the output is below any threshold, the presence of noise is assumed.