Wireless Messaging Glossary

Main Terms & Definitions

Alphanumeric: Messages comprised of both letters and numbers.
Coverage Area: Geographical area in which pagers or mobile phones can receive messages.
Digital: A digital signal is composed only of electrical pulses representing either zero or one. Because digital signals are made up only of binary streams, less information is needed to transmit a message. Digital encoding therefore increases the capacity of a given radio frequency. Furthermore, only digitized information can be transported through a noisy channel without degradation. Even if corruption occurs, as long as the one zero pattern is recognizable, the original information content can be perfectly replicated at the receiving end.
Frequency: Assigned channel space within the spectrum.
Numeric: Messages comprised simply of numbers and no letters. The character set used by "numeric pagers". This character set includes the numbers '0' to '9', punctuation such as a space(' '), hyphen('-'), and sometimes other symbols, such as "$."
Paging: To deliver a message to someone when their location is unknown through a wireless device usually known as a pager.
PCS: Narrowband Personal Communications Services — A new generation of digital, two-way, low powered wireless services in the 800 to 900 MHz bands that will support a wide range of services including confirmed delivery of message, full two-way data transfer, voice messaging and connectivity via the internet.
PET: Paging protocol that preceded TAP.
ReFlex: New 2-way wireless protocol developed by Motorola.
SNPP: Simple network paging protocol allows for messages to be sent through the Internet to pagers and cell phones.
TAP: Telelocator alphanumeric protocol allows for messages to be sent through modem to the paging terminal in a format that the paging terminal understands.
Terminal: The device on the tower that accepts messages in and controls the base station prior to the broadcasting of the message. In paging, this is a computer controlled switching system that accepts calls from the telephone network and controls the base stations used to signal pagers. The software in the terminal dictates many capabilities of the paging system.
Transmitter: Email setting to deliver to the carrier using SMTP protocol; this transmission is the least reliable of all of the accepted protocols.
UCP: Protocol common in Scandinavian countries; similar to TAP.
WCTP: Wireless communication transfer protocol allows for messages to be sent through the Internet to pagers and cell phones.

A

Alphanumeric Pagers: A term used to denote a pager equipped to receive both numeric and text messages.
Amplification: Process of increasing the strength of a signal, current, voltage or power.
Analog: Refers to a type of measurement in which the "line of measure" is continuous as compared to one which is discretely incremented.
Analog Transmission: Transmission of a continuously variable signal as compared to a discrete (digital) one.
Antenna: Device which radiates and/or receives radio signals.
ASCII: A code that represents letters, numerals, punctuation marks and control signals as seven bit groups. It is used as a standard code by the transmission of data. The values range from hex value 00 to hex value 7F.

B

Band: Range of radio frequencies between two defined limits which are used for a specific purpose.
Bandwidth: Portion of the frequency spectrum required to transmit desired information. Each radio channel has a center frequency and additional frequencies above and below this carrier frequency which is used to carry the transmitted information. The range of frequencies from the lowest to the highest used is called the bandwidth.
Baseband: Transmission of a digital or analog signal at its original frequencies. The signal is in its original form, not changed by modulation.
Baud Rate: The number of discrete signal events per second that occur on a communications channel.
Binary: Refers to the base-two number system. The system contains only two numbers, 0 and 1. In computer-like circuits, the presence of a voltage, current or other such signal indicates a "1" whereas the absence of the same signal indicates "0".
Bit: Contraction of binary digit. It is the smallest unit of information in a binary system.
Bits Per Second: (bps) — Rate at which bits of information are transmitted.

C

Cap Code: Every functioning pager within a paging system is assigned a unique cap code. A pager identifies which messages are intended for it by its unique cap code.
Carrier: Continuous frequency capable of being modulated or impressed with a second signal.
Carrier Frequency: Radio wave, current or voltage used for transmitting intelligence, usually the frequency of a radio channel.
Codeword: A contiguous set of bits that together form a piece of information. The codewords used in digital paging codes include redundant bits that allow a receiver to reconstruct the information if some of the bits were received incorrectly.

D

Decryption: Process of "unscrambling" an encrypted or coded message.
Digital Signal: Transmission signal that carries information in a discontinuous stream of on/off pulses.

E

Encoder: Converter used to create a specific addressed message.

F

FCC: Federal Communications Commission — The FCC has the authority to regulate all interstate communications originating in the United States.
FEC: Forward Error Correction — A method of increasing the reliability of data communication. In one-way communication channels, a receiver does not have the option to request a re-transmission if an error was detected. Forward Error Correction is a method of sending redundant information with the data in order to allow the receiver to reconstruct the data if there was an error in transmission.

G

GHz: GigaHertz — One GigaHertz is equal to one billion hertz.

H

Hertz: A measurement of frequency in cycles per second. One Hertz is one cycle per second.

I

Interface: Method or piece of equipment for interconnecting units or systems which may not be directly compatible.
Interference: Effects that occur when undesired signals inhibit or degrade the reception of a desired signal.
ISO: International Standards Organization — A body that sets standards and promotes their use throughout several industries around the world. Sometimes the ISO and CCITT standards overlap, as in the case of some networking protocols. In this case, protocols will often have two names, one under ISO and the other under CCITT.

K

KHz: KiloHertz — One kHz is equal to 1,000 Hertz.

L

LCD: Liquid Crystal Display.

M

MCD: Mobile Computing Device — The ultimate recipient of the data entered from the MED.
MED: Message Entry Device — A device which sends information into a paging network using TDP. This may be any type of device from a hand-held type of unit to a host computer.
MHS: Message Handling System — A general-purpose system used for receiving, storing, and sending messages with a consistent set of protocols to connect to external devices.
MHz: Megahertz — One MHz is equal to one million Hertz.
Modem: Interface device usually connected between a computer and telephone lines or a radio system.
Modulate: Vary the amplitude, frequency or phase of a radio signal in order to transmit intelligence.
Modulation: Information on a carrier signal by varying one or more of the signal's basic characteristics — frequency, amplitude and phase. Different modulation carries the information as the change from the immediately preceding state rather than the absolute state.

N

Nationwide Paging: Method of national or regional paging in which a single frequency is used throughout the nation (region) for sending messages to a paging system subscriber.
Numeric Paging: Numeric Paging is the most widely used type of paging. The caller simply calls your pager phone number and enters the number where you can reach them. (see also digital)

O

OSI: Open Systems Interconnect — An industry wide protocol standard consisting of seven well defined layers. TDP is modeled after this standard. A sub group of the ISO that defines communication protocols for inter-computer networking.

P

Parity: A simple error detection scheme. The method usually involves counting the '1' bits in a codeword and then setting an additional bit to either '1' or '0' depending on whether the original number of '1' bits was even or odd.
PCMCIA: Personal Computer Memory Card International Association — A standardized technology used to develop an expansion for portable devices (i.e. notebooks). In paging, these credit card sized devices support wireless connectivity.
PER: Packed Encoding Rules — A set of rules that specifies how ASN.1 defined information is encoded when transmitted, and how it is decoded when received. PER is a successor to the Basic Encoding Rules (BER). It is more efficient in terms of the number of bytes transmitted and the size of the generated encoder and decoder.
PMP: Paging Message Processor — A Radio Paging Terminal or equivalent message processing system.
POCSAG: Post Office Code Standard Advisory Group — This was a group formed by the British Post Office to design a non-proprietary digital paging code. The code that they designed is now implemented by most pager manufacturers and is the most widely used code to date. The POCSAG code, also known as RPC1 (a CCIR standard taken directly from POCSAG) can be operated at three speeds: 512, 1200, and 2400 bits per second. POCSAG is gradually being replaced by FLEX.
Protocol: The rules of order by which a communications network is operated.

R

Receiver: Device on the transmission line that converts a signal to whatever type of signal is needed to complete the transmission.
ReFlex: New two-way paging protocols developed by Motorola for enhanced paging services. ReFLEX 25 supports outbound transfer rates of up to 6,400 bits per second in a 25 kHz channel and 12,800 bits per second in a 50 kHz channel.
RF: Radio Frequency.
RRD: RF Receiving Device — The radio receiving device which receives over the air data and forwards it to the mobile computer.

S

Signal: Form of a radio wave in relation to the frequency serving to convey intelligence in communication.
Silent Alert: Non-audible signal in a beeper that discretely notifies individuals of incoming pages, typically by vibration.
Simulcast: Broadcasting a message over multiple transmitters throughout a geographical region at precisely the same time.
SMS: Short Messaging Service.
Sub Network: A way of denoting a group of network layers that appears as one to a higher protocol layer.

T

TCP: Telelocator Conversion Processor — A front end processor which executes the TFC process.
TDP: Telelocator Data Protocol — A suite of protocols used for sending messages from a computer, through a paging system, to a mobile receiving computer. Together, these protocols define the flow of messages from input devices through several processing steps until the entire message is received by an RF linked computer. The set is comprised of several protocols, including TME, TRT, and TMC.
Telecommunications: Communication process that allows the transmission of information from a sender to a receiver by means of an electromagnetic or light wave medium.
TFC: Telelocator Format Conversion — Describes how binary data messages may be forwarded to RF linked computers through the use of TAP protocol.
TNPP: A protocol used for moving pages from one paging system to another over the standard lines.
Transparency: A method for hiding "control" characters from a protocol processor in order to allow their inclusion inside a data message being carried by that protocol.
TRT: Telelocator Radio Transport protocol — The protocol that describes the format of data which is forwarded to RF receivers. This transport style protocol allows a receiver to collect several separate messages inside different pages and then piece them together into one proper message. The manner in which this data is inserted into any particular radio pager encoding format is specific to the particular manufacturer's radio receiver.
Two-Way: Communications that occur between communications radio stations, each having a transmitter and receiver. The stations may be in fixed locations, mobile or portable, in any combination.

U

UCP: Protocol common in Scandinavian countries; similar to TAP.

W

WAP: Wireless Application Protocol (WAP) is an open, global specification that empowers mobile users with wireless devices to easily access and interact with information and services instantly.
Watt: Basic unit of power. Equal to the voltage multiplied by the current.
WMF: Wireless Message Format — A standard format for presenting data received through a paging system to mobile computers. The application at the MED uses this format to encode binary data and control information to be sent to a remote device. This information is received completely intact by the MCD.