STANAG 4539


Overview:

The RapidM modems include the narrowband HF data modem waveforms which are in compliance with STANAG 4539.  This standard describes the Serial Tone Mode (STM) providing data rates ranging from 75 to 9600 bps coded and 12800 bps uncoded in a 3 kHz channel.

Status:

The STANAG 4539 (Edition 1) “Technical Standards for Non-Hopping HF Communications Waveforms” was released in Jun 2005.

Key Features:

  • Very Robust Traffic Waveform providing a 75 bps autobaud data modem for conveying data traffic over severely degraded channels as specified in STANAG 4415.
  • Low To Medium Data Rate Traffic Waveforms providing autobaud data modem with data rates ranging from 150 to 2400 bps coded as specified in MIL-STD-188-110 (Section 5.3).
  • High Data Rate Traffic Waveforms providing autobaud data modem with data rates ranging from 3200 to 9600 bps coded and 12800 bps uncoded. Specifically, Annex B of the STANAG 4539 standard specifies the HF Data Modem Waveforms for data rates above 2400 bps.
  • Non-Hopping TDMA Traffic Waveforms providing data modems for HF fixed frequency slotted TDMA operation. Specifically, Annex D of the STANAG 4539 standard specifies the modulation types and contents for three TDMA waveforms, WF1, WF2 & WF3.

Relevance:

  • The single tone PSK waveforms’ are important for backwards interoperability with NATO BRASS systems used by Navies.

Serial Tone Mode (STM):

The table below summarises the complete STANAG 4539 waveform suite. Included in the table are the modulation, code rate and interleaver settings for each data rate. The STANAG 4539 waveform includes tone excision whereby suppression of up to 4 tones is possible.  The inclusion of tone excision improves the waveform resilience and performance in the presence of channel interference.

Waveform Data Rate (bps) Modulation
Constellation
Coding Rate Interleaver Settings Tone Excision Capability
S 4539

 

75 C Walsh 1/2 Z, S, L YES
150 C BPSK 1/8 YES
300 C BPSK 1/4 YES
600 C BPSK 1/2 YES
1200 C QPSK 1/2 YES
2400 C 8-PSK 1/2 YES
2400 C VOICE 8-PSK 1/2 Z, S YES
3200 C QPSK 3/4 US, VS, S, M, L, VL NO
4800 C 8-PSK 3/4 US, VS, S, M, L, VL NO
6400 C 16-QAM 3/4 NO
8000 C 32-QAM 3/4 NO
9600 C 64-QAM 3/4 NO
12800 U 64-QAM None None NO

Table 1: STANAG 4539 – STM Waveform Suite

The following tables give performance results for the RM modems for various data rates. The results were measured using an HF Channel Simulator.

An AWGN channel is representative of ground wave propagation while the POOR channel represents skywave conditions. A RICEAN channel has a steady (specular) component and a fading component, thus representing a mixture of the ground and skywave propagation scenarios.

STANAG 4539
AWGN Channel (STANAG 4203 Filters included)

Data Rate [bps]

IB

SNR for BER=10-5[dB in 3kHz]

Mandatory Requirement Design Objective RM6 Measured
12800 N/A 28 25.7
9600 VL 22 20 19.5
8000 VL 19 17 16.4
6400 VL 16 14 13.7
4800 VL 14 12 11.2
3200 VL 9 7 6.6
RICEAN Channel (STANAG 4203 Filters included)

Data Rate [bps]

IB

SNR for BER=10-5[dB in 3kHz]

Mandatory Requirement Design Objective RM6 Measured
9600 VL 32 29 24.2
8000 VL 26 23 20.6
6400 VL 22 19 17.0
4800 VL 18 15 14.0
3200 VL 13 9.4
POOR Channel (STANAG 4203 Filters included)

Data Rate [bps]

IB

SNR for BER=10-5[dB in 3kHz]

Mandatory Requirement Design Objective RM6 Measured
9600 VL 32 29 27.6
8000 VL 28 25 23.5
6400 VL 24 20.8
4800 VL 21 18 17.0
3200 VL 15 12.6

Table 2: Performance: STANAG 4539


STANAG 4539 Modems

RapidM’s STANAG 4539 compliant modems include: