An Emission Designator code is associated with a frequency channel that gives information about the channel’s frequency bandwidth and the nature of the signal on that frequency.

Raveon’s FM Data Radios typically use these Occupied Bandwidths. See data sheets or contact sales team for detailed Occupied Bandwidth information.

If you need a different Occupied Bandwidth, contact Raveon’s sales or support team and we can setup a radio to other power and deviation settings to ensure it meets your bandwidth requirements.

What is an FCC Emission Designator?

For a wireless device, am Emissions Designators are a 6 to 8 character code identifying the electromagnetic modulation characteristics. Codes represent different features of wireless emissions from different products.

Emission Designators are used by governments including the FCC and ACMA.

Current Modern Emission Designators

Emission Designator consists of 7 characters as described here:

The first four characters identify the bandwidth required to transmit data at the rate with the required system performance that is used.

The fifth character is the type of modulation of the main carrier.

The sixth character is the signal modulating the RF carrier.

The seventh character is the type of information transmitted.

Modulating signal codes

The 6th character of the emission designator specifies the type of data that is being transmitted. Here is a list of transmission types:

• N – None Transmission. (RX only).
• A – Aural Morse Code telegraphy for people.
• B – Telegraphy for machines, RTTY, fast Morse Code.
• C – Analog fax.
• D – Data, telemetry, telecommand.
• E – Telephony, voice, broadcasting sound.
• F – Video, television.
• W – Combinations of the above
• X – All cases above not covered.

Modulation Type Codes

N   None
A   AM (Amplitude Modulation), double sideband, full carrier
H   AM, single sideband, full carrier
R   AM, single sideband, reduced or controlled carrier
J   AM, single sideband, suppressed carrier
B   AM, independent sidebands
C   AM, vestigial sideband  (commonly analog TV)
F   Angle-modulated, straight FM
G   Angle-modulated, phase modulation (common; sounds like FM)
D   Carrier is amplitude and angle modulated
P   Pulse, no modulation
K   Pulse, amplitude modulation (PAM, PSM)
L   Pulse, width modulation (PWM)
M   Pulse, phase or position modulation (PPM)
Q   Pulse, carrier also angle-modulated during pulse
W   Pulse, two or more modes used

Here is an example of an Emission Designator, that shows and explains the different items to indicate in the Emission Designator.

Emission Designator structure and Emission Designator Example for 11K0F1D 

Emission Designator structure and Emission Designator Example for 11K0F1D 

Calculating Emission Designation Bandwidth (BW)

The math for calculating bandwidth of an FM signal can be simple algebra.

BW = 2 x { Baud Rate + FM Peak deviation }

Baud Rate is: modulation frequency, is the highest frequency of the data rate you send out over the air. For voice communications, modulation frequency is generally accepted to be 3000 Hz. In a radio system with the peak deviation of 2.5 kHz, the Audio formula works out like this:

BW= 2 (3000 + 2500 ) = 11 kHz

For data communications, the formula is: Bandwidth = B + (K × Shift)
Where BW = (speed of transmission in baud) + (K × Frequency shift in hertz) In FSK mode the value of K is = 1.2. For example:

The bandwidth of a 3300-Hz shift, 9600 baud ASCII signal transmitted as a F1D emission on a wide-band channel :
BW = 9600 + (1.2 × 3300) = 13,560 Hz
At 4800 deviation, BW = 15kHz on wideband.

On a Narrow band channel, 4800 baud, 2.2kHz deviation
BW=4800+(1.2*2200) = 7440Hz

For FM modulation (FSK) data transmissions, the bandwidth formula can be: BW = Baud + 2 * FMdeviation * 1.2

The FCC shows Binary Frequency Shift Keying math:
Bn = 3.86D + 0.27R D=deviation R=data rate
4800baud at 2.3kHz deviation = 10.2kHz bandwidth.

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