MIL-STD-188-110C

Overview:

The RapidM modems include the narrowband and wideband HF data modem waveforms, which are in compliance with MIL-STD-188-110C. This version of the standard includes the wideband HF data modems spanning bandwidth from 3 to 24 kHz in 3 kHz steps, as described in Appendix D.

Status:

The third revision of the MIL-STD-188-110 “Military Standard Interoperability and Performance Standards for Data Modems” was released in April 2000. The updated MIL-STD-188-110C Appendix D WBHF waveform standard was ratified in 2011. It has since been superseded by later revisions, the current one being MIL-STD-188-110D (December 2017).

Key Features:

• Autobaud capable Single Sideband (SSB) Narrowband STM waveforms including the Legacy MS110A and the high data rates waveform modes of MS110B Appendix C, providing data rates above from 75 bps to 9600 bps in 3 kHz.
• Autobaud capable Single Sideband (SSB) Wideband STM waveforms described in Appendix D of the MIL-STD 188-110C standard, specifies wideband HF Data Modem Waveforms for bandwidths from 3 kHz to 24 kHz in 3 kHz steps. In 24 kHz, the data rates range from 600 bps to 120 000 bps.

Relevance:

• The 3 kHz bandwidth waveforms, as specified in MIL-STD 188-110C Appendix D, provides a better performance compared to the 75 bps to 2400 bps waveforms of the MS110A/MS110B specifications.
• The motivation for extending the HF bandwidths is to provide user bit rates up to 120 kbps, and allow users the option of selecting the bandwidth and modulation so as to optimize modem and ARQ (e.g. STANAG 5066 WB) performance.
• HF communication has generally been limited to narrower bandwidths and lower data rates compared to satellite communication. The availability of high data rate beyond line-of-sight (BLOS) communications without the use of satellites or radio-relay is important to provide satellite-like data services over HF.
• The higher data rates supported by the Appendix D waveforms are sufficient to support services not previously practical over HF radio, such as real-time video transmission.

Serial Tone Mode (STM) – Single Sideband:

The table below summarises the complete MIL-STD 188-110C Appendix D STM waveform suite. Included in the table is the data rate as a function of bandwidth, waveform number and modulation.

Table 1: MIL-STD-188-110C Appendix D – STM Waveform Suite