Multipath mitigation is a term typically used in
Code Division Multiple Access
Code-division multiple access (CDMA) is a channel access method used by various radio communication technologies. CDMA is an example of channel access method, multiple access, where several transmitters can send information simultaneously over ...
(CDMA) communications and in
GNSS
A satellite navigation or satnav system is a system that uses satellites to provide autonomous geopositioning. A satellite navigation system with global coverage is termed global navigation satellite system (GNSS). , four global systems are op ...
navigation to describe the methods that try to compensate for or cancel the effects of the
Non Line Of Sight (NLOS) propagation. The
multipath
In radio communication, multipath is the propagation phenomenon that results in radio signals reaching the receiving antenna by two or more paths. Causes of multipath include atmospheric ducting, ionospheric reflection and refraction, and refl ...
effect occurs when a signal is received not only through a
Line of Sight
The line of sight, also known as visual axis or sightline (also sight line), is an imaginary line between a viewer/ observer/ spectator's eye(s) and a subject of interest, or their relative direction. The subject may be any definable object taken ...
(LOS) path, but also through one or several NLOS paths.
The multipath, if not addressed or compensated, can significantly reduce the performance of the
communication
Communication is commonly defined as the transmission of information. Its precise definition is disputed and there are disagreements about whether Intention, unintentional or failed transmissions are included and whether communication not onl ...
and
navigation
Navigation is a field of study that focuses on the process of monitoring and controlling the motion, movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navig ...
receivers. Various multipath mitigation methods can be used to estimate and remove the undesired NLOS components.
Chip manufactures of CDMA and GNSS receivers, such as
Qualcomm
Qualcomm Incorporated () is an American multinational corporation headquartered in San Diego, California, and Delaware General Corporation Law, incorporated in Delaware. It creates semiconductors, software and services related to wireless techn ...
,
Leica Leica may refer to:
Companies
* Ernst Leitz GmbH, later divided into:
** Leica Biosystems GmbH, a cancer diagnostics company
** Leica Camera AG, a German camera and optics manufacturer
** Leica Geosystems AG, a Swiss manufacturer of surveying and ...
,
NovAtel,
Septentrio
Septentrio N.V. is a designer and manufacturer of high-end multi-frequency GNSS receivers. Its main target is to provide GNSS receiver boards and modules for further system integration by original equipment manufacturers (OEMs). Septentrio's co ...
, etc. typically have multipath mitigation algorithms supported by their
chipsets
In a computer system, a chipset is a set of electronic components on one or more integrated circuits that manages the data flow between the processor, memory and peripherals. The chipset is usually found on the motherboard of computers. Chipse ...
. One of the first works in the field of
GPS
The Global Positioning System (GPS) is a satellite-based hyperbolic navigation system owned by the United States Space Force and operated by Mission Delta 31. It is one of the global navigation satellite systems (GNSS) that provide geol ...
multipath mitigation is in
[Brekel1992]
References
*M. Z. H. Bhuiyan, J. Zhang, E.S. Lohan, W. Wang, and S. Sand,
Analysis of multipath mitigation techniques with land mobile satellite channel model in Radioengineering journal, ISSN 1210-2512, vol. 21(4), Dec 2012, pp. 1067-1078
huiyan2012*B. J. H. van den Brekel and D. J. R. van Nee, "GPS multipath mitigation by antenna movements," in Electronics Letters, vol. 28, no. 25, pp. 2286-2288, 3 Dec. 1992. (Brekel1992)
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Radio technology