RF Engineer Interview Questions And Answers

You can describe what you know about it, specific projects you have done, or relevant places you worked in - government, security, information technology industries, etc.

Begin with specific places you worked, like government agencies or manufacturing companies. You can then briefly add what exactly you did in RF engineering in each of those places.

Describe any jobs or assignments you were involved in with wireless telecommunication, with an emphasis on design, implementation, and optimization of networks. Describe responsibilities like initial system dimensioning and design, coverage and frequency planning, interference analysis, etc.

Give specific examples from personal experience: antennae selection, tilting (mechanical or electrical), antenna clearance, power settings, etc.

You can define these responsibilities, give examples of your experience performing them, and add information on your familiarity with relevant propagation tools, like Wizard, Planet, Tornado, etc.

If you did, describe how you chose candidates, and how you advertised and conducted the recruitment campaign. Talk about any presentations and manuals you might have made as part of coaching campaigns you participated in.

Describe anything related to communication with colleagues, clients, and management: presentations and reports, phone and online communication, client representation, coaching, etc.

If you do, describe budget and milestone reports you did, and strategies you developed, proposed, and implemented to achieve RF project milestones on time.

Radio-frequency engineering is a part of electrical engineering that deals with devices that are designed to operate in the radio frequency spectrum. These devices operate within the range of about 3 kHz up to 300 GHz.

RF engineering is incorporated into almost everything that transmits or receives a radio wave, which includes, but is not limited to, mobile phones, radios, Wi-Fi, and two-way radios.

RF engineering is a highly specialized field falling typically in one of two areas:

►Providing or controlling coverage with some kind of antenna/transmission system
►Generating or receiving signals to or from that transmission system to other communications electronics or controls.

RF energy is one form of electromagnetic energy that is a component of the electromagnetic spectrum, which covers microwaves, visible light and X-rays, as well as many more kinds of energy emissions. RF energy, sometimes called "RF emissions," "RF waves" or "RF fields," is generated when a source current, such as a transmitter, is fed to an antenna. This current excites electrons within the antenna and the energy moves outward in the form of an electromagnetic wave.

Probably the most important use for RF energy is in providing radio communication services to the public, industry and government. Radio and television broadcasting, cell phones, radio communications for emergency services, weather radar and satellite communications are examples of important applications. Non-communication uses of RF energy include industrial heating and microwave ovens. Some consumer uses of radio communication include baby monitors, garage door openers, cordless telephones, WI-FI, remote key-less car entry devices and various medical devices, just to name a few. As well, certain non-radio devices, including computers and other digital devices, also emit RF energy.

At radio communication and broadcasting installations, you will generally find radio transmitters and receivers, transmission lines and antennas, as well as their supporting structures. Radiocommunication and broadcasting transmitters are electronic devices that generate RF signals which carry the information intended for receivers. The signals are transmitted by antennas and then picked up by receivers (via receive antennas), which then extract the information carried, be it a cell phone conversation or a television program.

To protect the general public, Health Canada maintains its guideline document entitled Limits of Human Exposure to Radio frequency Electromagnetic Energy in the Frequency Range from 3 kHz to 300 GHz, which is commonly referred to as Safety Code 6. This document has been adopted by many organizations across Canada and is referred to in several regulations. Industry Canada has adopted this guideline for the purpose of protecting the general public.

Exposure to RF energy at levels below the regulatory limits is considered to be safe. These limits are based on the lowest exposure level at which the potential harmful effects to humans could occur. Safety factors are then incorporated to arrive at recommended exposure levels for protection of the general public.

Health Canada's guideline document and most other RF exposure standards specify "time-averaged" maximum exposure limits. The purpose is to "smooth out" the short-term highs and lows of the exposure intensity to arrive at an "average" with which to compare to the limit. The averaging time is the time period over which exposure is averaged. The averaging time should not be interpreted as the maximum allowable exposure time.

As per Health guideline document, it is permissible to exceed the recommended exposure limits for short periods of time as long as the average exposure over the averaging time (0.1 hour or 6 minutes) does not exceed the limit.

A biological effect occurs when a change can be measured in a biological system after an introduction of some type of stimulus (e.g. RF energy). The observation of a biological effect, in and of itself, does not necessarily suggest the existence of a health effect.

A biological effect only becomes a health effect when it causes detectable impairment of health. According to the World Health Organization, health is "a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity."

The biological effects from laboratory studies reported in scientific peer-reviewed literature include those related to changes in temperature, blood brain barrier, melatonin, calcium efflux, DNA damage and gene expression. However, not all these biological effects have been established or are considered to be health effects. For example, blood brain barrier and melatonin effects have not been consistently replicated. Studies on DNA strand breaks have also failed numerous independent attempts at confirmation and calcium efflux changes are considered to be more of a biological response than an adverse health effect.

Several laboratory studies have looked into whether RF energy can initiate and promote cancer. The overwhelming majority of these studies have found no evidence that RF energy damages DNA or that it is likely to act as an initiator or a promoter of carcinogenesis.

An "established effect" is one that, based upon peer-reviewed scientific reports, is demonstrated to be reproducible (in more than one laboratory), consistent (within the same laboratory and across other laboratories) and causal (due to the exposure agent). Although several articles in the scientific literature report RF biological effects within a study, these effects do not necessarily stand up to scientific rigour because they are often not reproducible within the same (or other) laboratories or are subsequently found to arise as a result of confounding factors such as sample/tissue heating or vibration.

An epidemiological study is the investigation of the occurrence and causes of health effects in human populations.

There have been numerous epidemiological studies on RF exposure and its impacts on human health. The majority of these studies have failed to find any association between such exposure and any adverse heath effects.

Signal modulation is a process whereby certain characteristics of a radio wave are varied with transmitted information (voice, pictures and data).

Different signal modulations in both analogue (e.g. AM and FM) and digital (numeric) formats have been used in radio communication. Although most radio technologies originally used analogue signals, modern wireless telecommunications use digital transmissions. Detailed scientific reviews conducted so far have not revealed any hazard specific to different RF modulations.

EHS is a term used to describe a variety of non-specific symptoms, such as headache, fatigue, nausea, ringing in the ears, digestive disorders, skin redness and burning sensations, which some individuals attribute to electromagnetic field (EMF) exposure.

At levels normally encountered in our daily lives, EMFs are unperceived by our senses. Although EHS symptoms are real, numerous scientific studies have failed to demonstrate that they are associated with EMF exposure. In studies where human subjects (including EHS sufferers) were intentionally exposed to EMFs, most individuals were unable to detect whether EMFs were present, or showed symptoms that did not correlate with their actual exposure condition. The causes of EHS symptoms are unclear. There are suggestions that they might arise from environmental factors unrelated to EMFs. It is the opinion of Health Canada that there is no scientific evidence that the symptoms attributed to EHS are indeed caused by exposure to EMFs.