Chapter 5 Acronyms Key
The following table expands the key acronyms used in this chapter.
Term |
Value |
|---|---|
μs |
microsecond or 1 × 10-6 second |
4G |
4th generation (mobile telecommunications system) |
BITS |
building integrated timing supply (SONET) |
cTE |
constant time error |
DPLL |
digital phase-locked loop |
dTE |
dynamic time error |
E1 |
2-Mbps (2048-kbps) signal (SDH) |
EEC |
Ethernet equipment clock |
ESMC |
Ethernet synchronization messaging channel |
FFD |
fractional frequency deviation |
FFO |
fractional frequency offset |
GPS |
Global Positioning System |
HPF |
high-pass filter |
ITU |
International Telecommunication Union |
ITU-T |
ITU Telecommunication Standardization Sector |
LPF |
low-pass filter |
LTE |
Long Term Evolution (mobile communications standard) |
max|TE| |
maximum absolute time error |
MTIE |
maximum time interval error |
NE |
network element |
OCXO |
oven-controlled crystal oscillator |
PLL |
phase-locked loop |
ppb |
parts per billion |
ppm |
parts per million |
PRC |
primary reference clock (SDH) |
PRS |
primary reference source (SONET) |
PRTC |
primary reference time clock |
PRTC-A |
primary reference time clock—class A |
PRTC-B |
primary reference time clock—class B |
PTP |
precision time protocol |
RMS |
root mean square |
SDH |
synchronous digital hierarchy (optical transport technology) |
SDO |
standards development organization |
SEC |
SDH equipment clock |
SONET |
synchronous optical network (optical transport technology) |
SSU |
synchronization supply unit (SDH) |
SyncE |
synchronous Ethernet—a set of ITU-T standards |
T1 |
1.544-Mbps signal (SONET) |
TCXO |
temperature-compensated crystal oscillator |
TDEV |
time deviation |
TE |
time error |
TIE |
time interval error |
VCO |
voltage-controlled oscillator |
VCXO |
voltage-controlled crystal oscillator |
XO |
crystal oscillator |