This article is about radio systems for point-to-multipoint communication. For the general concept, see multicast.
In telecommunications, point-to-multipoint communication (P2MP, PTMP or PMP) is communication which is accomplished via a distinct type of one-to-many connection, providing multiple paths from a single location to multiple locations.[1]
A point-to-multipoint radio base station manufactured by CableFree installed for a wireless internet service provider in Rotterdam. The station has four radio interfaces each connected to a separate sector antenna, each providing 90 degrees coverage. Within 20 km of this base station, customer-premises equipment with high gain directional antennas are installed on sites which can then connect to the base station to receive broadband data connections of typically 10–200 Mbit/s capacity.
In contemporary usage, the term point-to-multipoint wireless communications relates to fixed wireless data communications for Internet or voice over IP via radio or microwave frequencies in the gigahertz range.
Point-to-multipoint is the most popular approach for wireless communications that have a large number of nodes, end destinations or end users. Point to Multipoint generally assumes there is a central base station to which remote subscriber units or customer premises equipment (CPE) (a term that was originally used in the wired telephone industry) are connected over the wireless medium. Connections between the base station and subscriber units can be either line-of-sight or, for lower-frequency radio systems, non-line-of-sight where link budgets permit.[2] Generally, lower frequencies can offer non-line-of-sight connections. Various software planning tools can be used to determine feasibility of potential connections using topographic data as well as link budget simulation. Often the point to multipoint links are installed to reduce the cost of infrastructure and increase the number of CPE's and connectivity.[2]
Point-to-multipoint wireless networks employing directional antennas are affected by the hidden node problem (also called hidden terminal) in case they employ a CSMA/CA medium access control protocol. The negative impact of the hidden node problem can be mitigated using a time-division multiple access (TDMA) based protocol or a polling protocol rather than the CSMA/CA protocol.[3]
The telecommunications signal in a point-to-multipoint system is typically bi-directional, TDMA or channelized. Systems using frequency-division duplexing (FDD) offer full-duplex connections between base station and remote sites, and time-division duplex (TDD) systems offer half-duplex connections.
Point-to-multipoint systems can be implemented in licensed, semi-licensed or unlicensed frequency bands depending on the specific application. point-to-point and point-to-multipoint links are very popular in the wireless industry and when paired with other high-capacity wireless links or technologies such as free space optics (FSO) can be referred to as backhaul.
The base station may have a single omnidirectional antenna or multiple sector antennas, the latter of which allowing greater range and capacity.
^ abAnderson, Harry. R (2003). Fixed Broadband Wireless System Design. Chichester: Wiley. ISBN0-470-84438-8.
^"Point to Multipoint Wireless". fluidmesh.com. Retrieved 2015-08-12.
January 01, 1970
point, multipoint, communication, this, article, about, radio, systems, point, multipoint, communication, general, concept, multicast, telecommunications, point, multipoint, communication, p2mp, ptmp, communication, which, accomplished, distinct, type, many, c. This article is about radio systems for point to multipoint communication For the general concept see multicast In telecommunications point to multipoint communication P2MP PTMP or PMP is communication which is accomplished via a distinct type of one to many connection providing multiple paths from a single location to multiple locations 1 A point to multipoint radio base station manufactured by CableFree installed for a wireless internet service provider in Rotterdam The station has four radio interfaces each connected to a separate sector antenna each providing 90 degrees coverage Within 20 km of this base station customer premises equipment with high gain directional antennas are installed on sites which can then connect to the base station to receive broadband data connections of typically 10 200 Mbit s capacity Point to multipoint telecommunications is typically used in wireless Internet and IP telephony via gigahertz radio frequencies P2MP systems have been designed with and without a return channel from the multiple receivers A central antenna or antenna array broadcasts to several receiving antennas and the system uses a form of time division multiplexing to allow for the return channel traffic Modern point to multipoint links editIn contemporary usage the term point to multipoint wireless communications relates to fixed wireless data communications for Internet or voice over IP via radio or microwave frequencies in the gigahertz range Point to multipoint is the most popular approach for wireless communications that have a large number of nodes end destinations or end users Point to Multipoint generally assumes there is a central base station to which remote subscriber units or customer premises equipment CPE a term that was originally used in the wired telephone industry are connected over the wireless medium Connections between the base station and subscriber units can be either line of sight or for lower frequency radio systems non line of sight where link budgets permit 2 Generally lower frequencies can offer non line of sight connections Various software planning tools can be used to determine feasibility of potential connections using topographic data as well as link budget simulation Often the point to multipoint links are installed to reduce the cost of infrastructure and increase the number of CPE s and connectivity 2 Point to multipoint wireless networks employing directional antennas are affected by the hidden node problem also called hidden terminal in case they employ a CSMA CA medium access control protocol The negative impact of the hidden node problem can be mitigated using a time division multiple access TDMA based protocol or a polling protocol rather than the CSMA CA protocol 3 The telecommunications signal in a point to multipoint system is typically bi directional TDMA or channelized Systems using frequency division duplexing FDD offer full duplex connections between base station and remote sites and time division duplex TDD systems offer half duplex connections Point to multipoint systems can be implemented in licensed semi licensed or unlicensed frequency bands depending on the specific application point to point and point to multipoint links are very popular in the wireless industry and when paired with other high capacity wireless links or technologies such as free space optics FSO can be referred to as backhaul The base station may have a single omnidirectional antenna or multiple sector antennas the latter of which allowing greater range and capacity See also editBackhaul telecommunications Broadcasting networking Local Multipoint Distribution Service Multichannel Multipoint Distribution Service Wireless access pointReferences edit M Cover Thomas Joy A Thomas 1991 Elements of Information Theory Wiley Interscience ISBN 0 471 06259 6 a b Anderson Harry R 2003 Fixed Broadband Wireless System Design Chichester Wiley ISBN 0 470 84438 8 Point to Multipoint Wireless fluidmesh com Retrieved 2015 08 12 Retrieved from https en wikipedia org w index php title Point to multipoint communication amp oldid 1023039916, wikipedia, wiki, book, books, library,
