HF wideband

HF wideband

Beyond line of sight communications

BLOS communications – HF vs. SATCOM

High frequency (HF) hardware and software can be scaled to the mission at hand. Highly portable, HF radios can be used to equip units or teams that are hundreds of kilometers away from their headquarters (HQ). Conventional very high frequency/ultra-high frequency (VHF/UHF) radios only work in the line-of-sight range. By contrast, deployed HQs can use HF systems to stay in touch with their counterparts back home. Naval vessels and military aircraft use HF systems to keep in touch with other platforms, units or bases stationed hundreds or even thousands of kilometers away.

Increasingly, HF systems are seen as a reliable alternative to satellite communications (SATCOM). HF systems can securely carry voice and data traffic across similar international distances. By contrast, SATCOM systems are vulnerable to detection and jamming. SATCOM bandwidths may be saturated by other users at any given moment. HF systems can work in the long, beyond line-of-sight (BLOS) range, but without mesh networks or satellites. HF transmissions also have unique properties that make it difficult to determine their source. Even if their source can be determined, high frequency signals have inherent properties that make them difficult to jam.

The new HF wideband mode can significantly reduce link setup and data throughput times.

Rohde & Schwarz uses more than just the unique properties of HF systems to safeguard communications. The company has poured decades of experience with strong communications and transmission security (COMSEC/TRANSEC) into their HF products. Users can rest assured that HF communications systems from Rohde & Schwarz are secure.

High frequency communications

HF - No need for infrastructure

  • Very low operating costs
  • Reliable and proven technology (in service for decades)
  • Robust under all conditions – countless waveforms available for all demands
  • Secure communications (COMSEC and TRANSEC)
  • Up to date HF Radios are small, light and easy to use
Satellite communications

Satellite communications

SATCOM - Expensive infrastructure required

  • High operating costs
  • Growing demand is increasingly restricting satellite capacity
  • High risk of jamming, spoofing or even being totally disabled
  • Risk of getting allocated to a poor-quality channel
  • Can also be affected by environmental conditions (solar activities, covered sky-view, etc.)

National HF backbone

HF backbone networks are a backup for existing SATCOM networks and stand-alone systems in certain operations or theaters.

The backbone service provides HF communications to all defense ministries and defense departments, government departments, worldwide embassy networks and Partnership for Peace members.

It allows real-time strategic communications between ground stations, submarines, surface vessels, fixed wing aircraft and helicopters. A national HF backbone network requires minimal infrastructure and can communicate over long distances.

Typical HF backbone services include analog voice communications traffic (telephone patches) and digital communications traffic, such as digital voice (secure and non-secure), IP communications such as chat, email and HTTP exchanges, military messaging, application data and tactical data links (TDL) (Link 22; pictures and video).

Use cases include maritime patrols and repositioning, routine flight activities and humanitarian assistance and disaster response:

  • Intelligence links between maritime patrol aircraft and terrestrial command and support elements.
  • Repositioning activities for navy platforms, including meteorological and command data.
  • Establish source of real-time command and intelligence communications.
  • Provision of traffic, positioning, and navigation information and assistance.
  • Carrying emergency action messages.
  • Army aviation support for aeromedical evacuation.

In customs and border protection a national HF backbone helps:

  • Protect borders: A long-range border protection communications network can help inspect containers at sea, intercept suspicious vessels and patrol borders.
  • Ensure disaster resilience: A reliable emergency response communications network can help with real-time assessments and requests for necessary resources.
  • Enhance security: A secure communications network can help share intelligence between air, land, and sea assets to identify and pursue threats.
HF learning center

HF learning center

Ship-Shore-Ship Buffer (SSSB)

A real-time data link buffer system for data-exchange

The Ship-Shore-Ship Buffer (SSSB) is a real-time data link buffer system for exchanging data among naval forces, including airborne assets and associated units in the air defense ground environment. SSSB functions include data transmission and forwarding on multiple national and NATO data links including Link 1, Link 11, Link 11B and (in the future) Link 22. The SSSB generates a real-time common operational overview for air, surface and sub-surface elements.

The SSSB can support the exchange of information through NATO data links and is part of the command, control and intelligence (C3I) scenario between NATO and national armed forces.

Link 22 or NATO Improved Link Eleven (NILE) is a communications standard for tactical data links. During missions, Link 22 improves information distribution, relative navigation and identification capability to support tactical command and control among alliance members and with members of other alliances.

Link 22 can be employed in the HF range (2-30MHz) and UHF range (225-400 MHz). UHF is used for line-of-sight (LOS) communications, HF for links of up to 1,000 nm (1,852 km). Fixed-frequency modes as well as EPM (ECCM) modes are defined for both HF and UHF.

Various tests have been carried out with Rohde & Schwarz equipment in Germany, Finland and France. The tests demonstrated that software defined radios in the Rohde & Schwarz M3SR family – including R&S Series 4100 HF radios and R&S Series 4400 UHF radios – runs smoothly with all currently available Link 22 modems. Legacy and deployed radios can be upgraded to support the new tactical data link and safeguard customer investments.

Rohde & Schwarz participates in many international Link 22 conferences, workshops and demonstrations, contributes actively toward the optimization and standardization of the new tactical data link and provides input to various NATO working groups.

HF at a glance

HF at a glance

Spend 80 seconds with HF at a glance in this short video and learn more about the oldest form of communications.

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HF wideband

HF wideband

Spend 80 seconds with HF wideband in this short video and learn what HF wideband is all about.

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Related resources

Related HF communications webinars

HF in a nutshell

This webinar is the first in a series covering HF topics and will illustrate that HF communications is in no way your grandparents' technology, but rather THE communications solution for the future.

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Part 1 of HF wideband - 4th generation of HF communications

Learn more about relevant standards and practical performance expectations of HF wideband communications in this first session of the “HF Wideband - 4th generation HF communications” webinar series.

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Part 2 of HF wideband - 4th generation of HF communications

Learn more about physical basics, effects and requirements for HF devices in the second session of the “HF Wideband - 4th generation HF communications” webinar series.

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Newsletter registration

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New product introduction

Introducing the new HF high-power transmitters for beyond line of sight communications.

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Liquid cooling

Learn more about the liquid cooling technology of the HF high-power transmitters for Ship-to-Shore communications from Rohde & Schwarz.

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Learn more about the unmatched reliability of the HF high-power transmitters for Ship-to-Shore communications from Rohde & Schwarz.

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Total cost of ownership

Learn more about total cost of ownership of the HF high-power transmitters for Ship-to-Shore communications from Rohde & Schwarz.

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