| ONA |
open network
architecture |
| OSI |
open switching
interval |
| OSI |
Open Systems
Interconnection |
| OSI-RM |
Open Systems
Interconnection--Reference Model |
| P/A R |
peak-to-average
ratio |
| P/P |
point-to-point |
| PAD |
packet
assembler/disassembler |
| PAL |
phase alternation by
line |
| PAL-M |
phase alternation by
line--modified |
| PAM |
pulse-amplitude
modulation |
| PAMA |
pulse-address multiple
access |
| PAMR |
Public Access Mobile
Radio |
| PC |
carrier power (of a
radio transmitter) |
| PC |
personal
computer |
| PCB |
printed circuit
board |
| PCB |
power circuit
breaker |
| PCIA |
Personal Communications
Industry Association |
| PCM |
pulse-code
modulation |
| PCM |
plug compatible
module |
| PCM |
process control
module |
| PCMCIA |
Personal Computer memory
Card International Association |
| PCN |
Personal Communications
Networks (Europe) |
| PCS |
Personal Communications
Services operating in the 1.9GHz band. Primarily in North America. Includes
three technologies: GSM 1900, CDMA and TDMA (IS-136, or D-AMPS) |
| PCS |
personal communications
system |
| PCS |
plastic-clad silica
[fibre] |
| PCS |
personal communications
system |
| PCS |
plastic-clad silica
[fiber] |
| PCSR |
parallel channels
signaling rate |
| PDC |
Personal Digital
Cellular (Japan) used to be called JDC |
| PDM |
pulse delta
modulation |
| PDM |
pulse-duration
modulation |
| PDM |
pulse-duration
modulation |
| PDN |
public data
network |
| PDS |
protected distribution
system |
| PDS |
protected distribution
system |
| PDS |
program data
source |
| PDT |
programmable data
terminal |
| PDU |
protocol data
unit |
| PE |
phase-encoded
[recording] |
| PEP |
peak envelope power (of
a radio transmitter) |
| pF |
picofarad |
| PF |
power factor |
| PFM |
pulse-frequency
modulation |
| PHS |
Personal Handyphone
System (Japan) |
| PI |
protection
interval |
| PIC |
plastic insulated
cable |
| PIV |
peak inverse
voltage |
| PL/I |
programming language
1 |
| PLA |
programmable logic
array |
| PLL |
phase-locked
loop |
| PLN |
private line
network |
| PLR |
pulse link
repeater |
| PLS |
physical signaling
sublayer |
| PM |
phase
modulation |
| PM |
mean power
polarization-maintaining [optical fibre] |
| PM |
preventive
maintenance |
| PM |
pulse
modulation |
| PM |
mean power
polarization-maintaining [optical fiber] |
| PMB |
pilot-make-busy
[circuit] |
| PMO |
program management
office |
| PMR |
Private Mobile
Radio |
| POI |
point of
interface |
| POP |
point of
presence |
| POSIX |
portable operating
system interface for computer environments |
| POTS |
plain old telephone
service |
| PP |
polarization-preserving
[optical fibre] |
| P-P |
peak-to-peak
[value] |
| PPM |
pulse-position
modulation |
| PPS |
pulses per
second |
| PRF |
pulse-repetition
frequency |
| PRM |
pulse-rate
modulation |
| PRR |
pulse repetition
rate |
| PS |
permanent
signal |
| psi |
pounds [force] per
square inch |
| PSN |
public switched
network |
| p-static |
precipitation
static |
| PSTN |
public switched
telephone network |
| PTF |
patch and test
facility |
| PTM |
pulse-time
modulation |
| PTO |
Public
Telecommunications Operator |
| PTT |
postal, telephone, and
telegraph |
| PTT |
push-to-talk
[operation] |
| PTTC |
paper tape transmission
code |
| PTTI |
precise time and time
interval |
| PU |
power unit |
| PUC |
public utility
commission |
| PVC |
permanent virtual
circuit |
| PVC |
polyvinyl chloride
[insulation] |
| pW |
picowatt |
| PWM |
pulse-width modulation
[deprecated] |
| pWp |
picowatt,
psophometrically weighted |
| pWp0 |
picowatts, relative to a
0TLP |
| PX |
peak envelope
power |
| PX |
private
exchange |
| pX |
peak envelope power (in
dB) |
| PX |
peak envelope
power |
| PX |
private
exchange |
| pY |
mean power [in
dB] |
| PY |
mean power [in
watts] |
| pZ |
carrier power [in
dB] |
| PZ |
carrier power [in
watts] |
| QAM |
quadrature amplitude
modulation |
| R/T |
real time |
| RCC |
radio common
carrier |
| RCVR |
receiver |
| RDF |
radio
direction-finding |
| RFI |
radio frequency
interference |
| ROI |
Return On
Investment |
| ROSE |
remote operations
service element protocol |
| RTA |
remote trunk
arrangement |
| RTS |
request to
send |
| RTTY |
radio
teletypewriter |
| RTU |
remote terminal
unit |
| RTX |
request to
transmit |
| RVA |
reactive
volt-ampere |
| RWI |
radio and wire
integration |
| S/R |
send and
receive |
| SCR |
semiconductor-controlled
rectifier |
| SCR |
silicon-controlled
rectifier |
| SF |
single-frequency
[signaling] |
| SIM |
Subscriber
Identification Module (GSM) |
| SMR |
Specialised Mobile Radio
(USA) |
| SMS |
Short Messaging Service.
Further info in Technical Archive. |
| SSB |
single-sideband
[transmission] |
| SSB-SC |
single-sideband
suppressed carrier [transmission] |
| SWR |
standing wave
ratio |
| SX |
simplex
signaling |
| TACS |
Total Access
Communications System (900 MHz.) Analog standard similar to AMPS |
| TCC |
telecommunications
center |
| TDM |
time-division
multiplexing. Further info in Technical
Archive. |
| TDMA |
Time Division Multiple
Access (IS-136, also known as D-Amps). Further
info in Technical Archive. |
| TEMS |
telecommunications
management system |
| TETRA |
Trans European Trunked
Radio |
| TGM |
trunk group
multiplexer |
| TIA |
Telecommunications
Industry Association |
| TIP |
terminal interface
processor |
| TSP |
Telecommunications
Service Priority [system] |
| TSR |
telecommunications
service request |
| TSR |
terminate and stay
resident |
| UMTS |
Universal Mobile
Telephone Service. Further info in Technical
Archive. |
| VF |
voice
frequency |
| VFCT |
voice frequency carrier
telegraph |
| VFDF |
voice frequency
distribution frame |
| VFO |
variable-frequency
oscillator |
| VRC |
vertical redundancy
check |
| WADS |
wide area data
service |
| WAIS |
Wide Area Information
Servers |
| WAN |
wide area
network |
| WAP |
Wireless Application
Protocol. Further info in Technical
Archive. |
| WATS |
Wide Area
Telecommunications Service |
| WATS |
Wide Area
Telecommunications Service |
| X.25 |
International Standard
for packet switched networks |
| Zo |
characteristic
impedance |
| 0TLP |
zero transmission level
point |