RIM 902M, Integrator Manual

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54 Glossary of terms: Shielding
Integrator’s Guide – RIM 902M OEM Radio Modem
Term: Meaning:
OEM
Original Equipment Manufacturer. Usually implies that
the “OEM product” is re-labelled with another
manufacturer’s name. The RIM 902M is designed to be
embedded in OEM terminals, PCs and data gathering
equipment, and as such the equipment it is embedded in
will not normally carry RIM’s name.
OSI
The Open Systems Interconnection model allows different
systems, following the applicable standards, to
communicate openly with each another.
Polarity Direction of current flow. Connecting some cables with the
wrong polarity (i.e. backward) may damage the device.
Radio Modem
A device which provides modulation and demodulation for
a radio frequency communications system.
Radiation In this document, “radiation” refers to the emission of
electromagnetic energy in the radio frequency (RF) band.
Do not confuse this with radioactive particle emissions
caused by nuclear reactions.
RAP Radio Access Protocol. An alternative to the MASC
protocol, found on the RIM
902M. Provides simpler
implementation and faster, reliable operation.
Return Loss A measure of antenna matching.
RF Radio Frequency.
RS-232 The standard asynchronous serial communications
interface used by most existing personal computers and
mini-computers. Usually refers to both the
communications protocol and the electrical interface.
SMA An RF connector type.
TTL Transistor-Transistor Logic. Used in digital circuits. Low
(0) is represented by ~0 V and High (1) is ~5 V.
Type Approvals These approvals are required by most governments before
radio transmitters and equipment containing radio
transmitters can be used. In the USA, a device must be
tested and certified by an independent lab which is
recognized by the FCC.
UART Universal Asynchronous Receiver/Transmitter. Used as an
interface between a microprocessor and a serial port.
VSWR
Voltage Standing Wave Ratio. A measure of antenna
matching. See Chapter 5, Antenna Integration.