Codan Radio Communications UT-4E900 User Manual

MT-4E VHF & UHF Receiver & Transmitter Instruction Manual

IM08-MT-4E-TXRX-P1162

GloSSaRy oF tERMS

Bandwidth 

The difference between the limiting 

frequencies of a continuous frequency band. 

Typically measured in kilohertz. May be 

considered the amount in kilohertz required 

for a single communications channel.

BER 

BIT Error Rate.

BPS 

BITs Per Second – a data rate measure.

C4FM 

Constant Envelope 4-Level Frequency 

Modulation – an FM transmitter which uses 

Quadrature Phase Shift Keying (QPSK) 

modulation to work with a compatible 

frequency discriminator detection (CFDD) 

receiver.

Channel 

A single unidirectional or bidirectional path 

for transmitting or receiving, or both, of 

electrical or electromagnetic signals.

Channel Spacing 

Typically measured in kilohertz from the 

center of one channel to the center of the 

next-adjacent channel. May, or may not, be 

identical to bandwidth.

Common Air Interface (CAI) 

A radio-to-radio signal path defined in terms 

of Access Method, Modulation Scheme, 

Vocoding Method, Channel Data Rate and 

Channel Data Format.

CTCSS 

Abbreviation for “Continuous Tone-Controlled 

Squelch System.”

DCS 

Digital Coded Squelch.

DSP 

Digital Signal Processor – a specialized 

microprocessor.

DTMF 

Dual-Tone Multi-Frequency – a signaling 

scheme used by the telephone system in 

which two voice band tones are generated 

for each keypad key press.

Encryption 

A coding of plain text (or clear voice) into 

unintelligible forms for secure transmission. 

Error Correction 

Digital coding technique for detecting and 

correcting information transmission errors.

FCC 

Federal Communications Commission.

Firmware 

Software that is permanently stored in a 

hardware device, and allows reading and 

executing, but not writing or modifying the 

software.

I

/O 

Input / Output

ISO 

International Standards Organization

LSB 

Least Significant BIT.