Radiolocation

Radiolocation, also known as radiolocating or radiopositioning, is the process of finding the location of something through the use of radio waves. It generally refers to passive uses, particularly radar—as well as detecting buried cables, water mains, and other public utilities. It is similar to radionavigation, but radiolocation usually refers to passively finding a distant object rather than actively one's own position. Both are types of radiodetermination. Radiolocation is also used in real-time locating systems (RTLS) for tracking valuable assets. An object can be located by measuring the characteristics of received radio waves. The radio waves may be transmitted by the object to be located, or they may be backscattered waves (as in radar or passive RFID). A stud finder uses radiolocation when it uses radio waves rather than ultrasound. One technique measures a distance by using the difference in the power of the received signal strength (RSSI) as compared to the originating signal strength. Another technique uses the time of arrival (TOA), when the time of transmission and speed of propagation are known. Combining TOA data from several receivers at different known locations (time difference of arrival, TDOA) can provide an estimate of position even in the absence of knowledge of the time of transmission. The angle of arrival (AOA) at a receiving station can be determined by the use of a directional antenna, or by differential time of arrival at an array of antennas with known location. AOA information may be combined with distance estimates from the techniques previously described to establish the location of a transmitter or backscatterer. Alternatively, the AOA at two receiving stations of known location establishes the position of the transmitter. The use of multiple receivers to locate a transmitter is known as multilateration. Estimates are improved when the transmission characteristics of the medium is factored into the calculations. For RSSI this means electromagnetic permeability; for TOA it may mean non-line-of-sight receptions.

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EE-442: Wireless receivers: algorithms and architectures

The students will learn about the basic principles of wireless communication systems, including transmission and modulation schemes as well as the basic components and algorithms of a wireless receive

Radiolocation

Radio

Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 3,000 gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna which radiates the waves, and received by another antenna connected to a radio receiver. Radio is widely used in modern technology, in radio communication, radar, radio navigation, remote control, remote sensing, and other applications.

Radiodetermination

As defined by FS-1037C and ITU Radio Regulations, radiodetermination is: "the determination of the position, velocity or other characteristics of an object, or the obtaining of information relating to these parameters, by means of the propagation properties of radio waves." There are two main fields to radiodetermination: radionavigation: "used for the purposes of navigation, including obstruction warning", which is mainly active; radiolocation: "used for purposes other than those of radionavigation", which is mainly passive.

Multipath Channels with ISI EE-442: Wireless receivers: algorithms and architectures

Discusses the impact of multipath channels with ISI on wireless receivers and how to mitigate their effects.

Wireless Receivers: Parameter Estimation EE-442: Wireless receivers: algorithms and architectures

Covers the challenges and techniques of parameter estimation in wireless receivers.

Wireless Localization Techniques COM-405: Mobile networks

Explores wireless localization techniques, including RSSI, trilateration, and advanced methods for accurate distance measurement in wireless networks.