Communications Systems Glossary

Radio frequency (RF).  Radio frequency describes the range of frequencies used for radio communications (across a radio channel).

Rayleigh fading.  Rayleigh fading is fading in a channel due to the interference caused to the main signal by the same signal arriving over many different paths, resulting in out-of-phase components incident at the receiver.

Reed-Solomon code (RS code).  The Reed-Solomon code (RS code) is an important subclass of non-binary BCH error-correcting codes in which the encoder operates on multiple bits rather than individual bits.

Relay.  A relay is used to pass on a signal, normally after retiming and regenerating it.

Repeater.  A repeater is a physical layer (Layer 1) device that interconnects two local area networks (LANs).

Resistance.  The ability of the wire to conduct is called conductance, but this property of the wire is normally considered in terms of how it restricts the flow of electrons, that is its resistance.

Resistor.  A resistor is a circuit component that has resistance.

Resting frequency.  The resting frequency is the frequency of an FM carrier when no modulating signal is present. The presence of a modulating signal will cause the carrier to shift away from the resting frequency.

Ring topology.  The ring topology is a local area network (LAN) topology in which the medium forms a loop to which workstations are attached.

Rivest-Shamir-Adleman algorithm (RSA algorithm).  The Rivest-Shamir-Adleman algorithm is a popular public-key encryption algorithm.

RJ # connector.  The RJ-11 connector is a four-wire modular connector used for telephone and modem connection. RJ-45 is the larger 8-wire modular connector used for 10BaseT Ethernet.

Router.  A router is a network layer (Layer 3) device that interconnects two local area networks (LANs).

Routing algorithm.  One of several algorithms used to determine how to transmit a message from its source to its destination across a network (that is, between network nodes).

Routing table.  A routing table is a database containing network node and terminal addresses as well as the path to be used in transmitting data between nodes.

Rx.  Rx is an abbreviation for ‘receive’.

Book Lists

If you wish to propose new entries to be added to this glossary, please contact Argos Press. Please contact Argos Press for information on licensing Argos Press content (such as this glossary entry on Communications Systems). © Argos Press Pty Ltd, Canberra, 2003-2004. All rights reserved.

Our other resources include Antennas, Appliances, Broadband Internet, CDMA, Communications Systems, GSM, Modems, Project Management, Radar, Risk Management and Decision Making, Satellite Communications, SMS, Speakers, Systems Engineering, Team Building, Time Management, Transmitters and Receivers, and XML.