An infrared sensor is a device that emits and/or receives infrared waves in the form of heat. While most infrared sensors transmit and receive infrared waves, some can only receive them. These types of infrared sensors are known as Passive Infrared Sensors (PIR sensors) or motion detectors. What is an Infrared Detector? An infrared detector …
dBm is the standard unit of measure for levels of power based on a one milliwatt (mW) reference signal. The dBm measurement is very similar to dB (decibel); however, dB is a relative measure of the power of an input signal while dBm is always an absolute value based on a single milliwatt. If there …
A multivibrator is a device that changes between two states and its own design or an external force powers it. For example, a weight that is placed on a suspended spring will extend the spring to its maximum length as gravity weighs down on it. When the spring is stretched to its maximum length, however, …
Amplitude modulation is a type of modulation where the carrier signal’s amplitude is varied in accordance with the information bearing signal. The amplitude modulated signal’s envelope or boundary embeds the information bearing signal. The total power of the transmitted signal varies with the modulating signal, whereas the carrier power remains constant. A nonlinear device combines …
A thermoelectric generator is a solid-state device that works similar to solar panels but converts heat, rather than sunlight, directly into electricity. A thermoelectric generator is usually made of bismuth telluride semiconductor junctions that are only several millimeters thick. This differs drastically from the bimetallic junctions that were previously used, which were much thicker. Thermoelectric …
A decoupling capacitor (bypass capacitor) is a device that separates current and voltage levels from two separate sections of the same electronic device. Decoupling capacitors are useful in situations that require an electronic device to fluctuate current or voltage levels without straining the power supply. Decoupling capacitors can be used in electronic devices that have …
In a very simple sense, a capacitor is a device that stores energy in an electric field between two charged "plates" for a short period of time. The electric charge is then used or dissipated at an appropriate time. The capacitor essentially works along the same lines as the battery you might find in a …
Portable radios are limited in the power at which they can transmit, usually somewhere between .5 watts and 5 watts. A very rough rule of thumb is that one watt equals one mile of range over flat and open terrain. Buildings and mountains will, of course, greatly modify effective range. When two radios communicate directly …
GPS – A Short Introduction GPS, which stands for Global Positioning System, is a satellite navigation system that can ascertain the latitude and longitude of a GPS receiver device on the Earth. The GPS consists of more than two dozen global positioning satellites orbiting the earth. Each satellite transmits radio signals, which can help determine …
QPSK (Quadrature Phase Shift Keying) is a phase modulation algorithm. Phase modulation is a frequency modulation version where the carrier wave’s phase is modulated to encode bits of digital information in each phase change. The “PSK” in QPSK refers to the use of Phased Shift Keying. Phased Shift Keying is a form of phase modulation …