STANAG 4539 Decoder

 

Availability

 

SkySweeper STD : NO

SkySweeper STD+ : YES

SkySweeper PRO : YES

 

General Description

This mode is known as several names like MIL-STD-188-110A/B, FED-STD-1052 and STANAG 4539. The mode consists of several sub modes (75-2400 bps) and two different interleaving options (short and long). 75B is the frequency hopping variant and all the others are fixed mode variants. The receiver should be in USB mode and provide flat frequency response from 600 Hz to 3000 Hz. The center frequency is at 1800Hz. SkySweeper supports also possibility to set the center frequency to 1500 Hz in case of bad frequency response of analog filters around 3000Hz. The decoder identifies automatically the mode and the interleaver, so it is recommended to set the decoder to "Auto" mode. It is also possible to set the decoder to the desired mode. Auto mode detection is then disabled.

 

Configuration

Pressing the ‘Config’ button opens the following Configuration dialog box.

 

 

 

 

Parameters

Mode

This selects the mode based on the net bit rate. ‘Auto’ means the automatic mode search.

 

Interleaver

This selects the used interleaver (short/long).

 

Carrier

This selects the carrier frequency (1500/1800Hz). The 1800 Hz is the standard. The1500 Hz should be used only in cases when the frequency response of the receiver filters is not optimal.

 

Modem ASCII Settings

The ASCII mode is configured here:

- number of ASCII data bits (4 – 8, all)

- parity bit (None, Even, Odd)

- Number of start bits (0 or 1)

- Number of stop bits (0,1 or 2)

 

If all is selected as a number of data bits, all received bits including start, stop and parity bits will be displayed by the bit tool. The bit tool is included in SkySweeper PRO.

Typically STANAG modem uses 7N1 (1 start bit, 7 ASCII data bits, no parity, 1 stop bit) or 8N1 (1 start bit, 8 ASCII data bits, no parity, 1 stop bit) formats. STANAG decoder own display supports only ASCII characters. STANAG decoder can be used with Bit Analyser tool, which supports many character sets.

 

 

Enable STANAG 5066 Parser

If check box selected enables STANAG 5066 Message Parser, which can be configure by pressing configure button. Parser can be used only in Message Mode.

 

Print Time Stamps

If checked time stamp is printed after every message.

 

RX Modem Data Print Options

These are the decoder print options. The data can be printed in the binary, hexadecimal, decimal or string format.

 

FFT

The ‘FFT’ button opens and closes the power spectrum window. You can, for example, close the power spectrum window when the decoder has been locked onto the correct frequency in order to get more space for the text window.

Save

The save button opens the log file control dialog, which is used to open or close a log file. The detector text window can be also saved into file or sent into socket.

Lock

‘Lock’ doesn’t have any effect in STANAG4539.

Reset

The ‘Reset’ button resets the decoder and clears the text window.