The RM2 HF & V/UHF Modem is a compact data modem designed for governmental agencies and NGOs requiring standards-compliant HF email services. The advanced unit supports both beyond-line-of-sight (BLOS) HF data modem and 2G ALE capacities for long-distance communication, as well as a VHF data modem for faster email delivery over line-of-sight (LOS) VHF channels.

Capable of establishing long-distance communication links up to 10,000 km, the RM2 achieves data rates of 9600 bps over a standard 3 kHz HF (SSB) connection and up to 96000 bps over a 24 kHz V/UHF radio link. To combat interference and noise, the RM2 leverages RapidM’s advanced HF modem technology, utilising adaptive equalisation and in-band distortion management. This ensures extended communication ranges and increased data throughput.

The RM2 offers versatile deployment options and can be easily used in desktop, vehicular and marine installations. Additionally, this modem can function as a standalone raw data modem and ALE controller, providing a single hardware solution that combines 2G ALE, MS110A, and MS110B functionalities in one compact package. It is further designed to operate in conjunction with an external STANAG 5066 ARQ server, such as the RC50 Email Communications Suite, enhancing its operational flexibility.

Its V/UHF waveforms are ideal for high-speed mobile data communication applications. The modem’s high-performance Doppler tracking allows operation at speeds up to 250 km/h (at 80 MHz). Its configurable bandwidth (24, 12, 9, 6, or 3 kHz) ensures compatibility with various radio capabilities. Lower data rates (PSK modulation) cater to radios with non-linear power amplifiers, while higher rates use QAM and require linear PAs or can operate with wideband FM or AM radios.

The RM2’s capabilities are determined by its software pack, with different versions catering to specific needs:

• M4: HF Modem (SSB, S4539, Up to 9600 bps)
• L1: V/UHF (24 kHz, Up to 96000 bps)
• L2: V/UHF (12 kHz, Up to 48000 bps)

An optional 2G ALE Controller Software Option is available for the M4 software pack to further enhance its capabilities.

Control of the RM2 is facilitated via a serial or Ethernet interface using the RapidM RIPC/RAP1 protocol. Data can be transferred through remote-control interfaces or a dedicated serial interface. This raw data interface supports asynchronous DTE devices (TX, RX, RTS/CTS, and DCD signals are available). The data interface offers FEC without ARQ. Radio interfacing is achieved using industry-standard 600 Ohm audio transmit and receive lines, as well as a PTT line. The radio can also be controlled by the optional ALE function embedded in the RM2 via the radio control port.

Combining robust performance, advanced features, and versatile deployment options, the RM2 is an ideal solution for a wide range of secure and reliable long-distance data communication needs.