Wireless Sensor Network Acronyms

 

ACK

Acknowledgement

Packet or transmission got through OK

ACL

Access Control List

 

AM

Amplitude Modulation

 

AP

Access Point

ARQ

Automatic Repeat reQuest

Sometimes called link level ACK or L2 ACK

ASK

Amplitude Shift Keying

A form of AM communication

BER

Bit Error Rate

 

CDMA

Code Division Multiple Access

 

CMOS

Complementary Metal Oxide Semiconductor

The standard family of processes used to manufacture integrated circuits.

CSMA

Carrier (or Channel) Sense Multiple Access

The channel is sensed before transmission is initiated.  If the channel is busy, transmission is delayed.  In some cases (e.g. Ethernet) the channel can be sensed during communication as well, in which case collisions can be detected (CSMA-CD).  In wireless this is generally not possible, and only a subset of collisions can be avoided (CSMA-CA).

dB

decibel

One tenth of a Bell.  1 Bell =  a factor of 10 in power.

dBm

deciBels relative to a milliWatt

1 Bell is an order of magnitude in power, so 10 deciBels relative to a milliWatt is 10mW.  -10 dBm = 0.1mW.  -90dBm = 1 picoWatt

ESA

Electrically Small Antenna

Any antenna for which 2pa/l < 1, where 2a is the maximum dimension of the antenna.

FEC

Forward Error Correction

 

FER

Frame Error Rate

 

FM

Frequency Modulation

 

FSK

Frequency Shift Keying

A form of FM communication

IETF

Internet Engineering Task Force

The organization that defines all of the internet protocols like IP, TCP, http, ftp, … www.ietf.org

ITU

International Telecommunications Union

Major standards body.

MAC

Medium Access or

Medium Access Control

The Medium Access Layer is a sub-layer of the Data Link Layer, layer 2

 

 

Message Authentication Code

In wireless communications this is usually called a MIC to avoid confusion with the Medium Access layer.

MIC

Message Integrity Code

 

NACK

Negative ACK

Packet or transmission did not get through OK

NET

Network layer

 

OOK

On Off Keying

A form of AM communication

OQPSK

Offset QPSK

RF modulation used by 802.15.4 in the 2.4GHz band

OSI

Open System Interconnection

A 7 layer model for representing the hierarchy of communication systems.  Generally given as: application, presentation, session, transport, network, data link, physical

PDR

Packet Delivery Rate (or Ratio)

The fraction of packets that make it through a single hop with no errors.

PDU

Protocol Data Units

Data exchanged between layers in an OSI stack.

PER

Packet Error Rate

 

PHY

Physical layer

 

PM

Phase Modulation

 

PSDU

Physical layer Service Data Unit

 

PSK

Phase Shift Keying

A type of RF modulation, contrast AM and FM

QPSK

Quadrature PSK

 

RF

Radio Frequency

 

RSSI

Received Signal Strength Indicator

RSSI is a measure of how much power was received by the radio.  Usually this is during reception of a packet, but sometimes just sampling the noise on the channel.  RSSI is usually measured in dBm

TDMA

Time Division Multiple Access

 

TDOA

Time Difference of Arrival

Used in RF location systems

TOF

Time of Flight

 

TSMP

Time Synchronized Mesh Protocol

 

WSN

Wireless Sensor Networks