Draft Manual On HF Data Link (HFDL) Technical Details


1.1 The purpose of this manual is to provide additional technical details for the link and subnet work layers of the HF data link (HFDL) system. These specifications were developed by the AMCP in conjunction with the Standards and Recommended Practices (SARPs) which are incorporated in Annex 10, Volume III, Part I, Chapter 11. States should ensure that, in the interest of interoperability, HFDL systems are operated in accordance with these specifications.

1.2 ICAO will continue to develop the material in this manual through the appropriate channels. Due account will be taken of the need to ensure, to the maximum extent practical, compatibility with the current specifications with a view to avoid the requirement to retrofit aircraft with new systems.


2.1 Reliable link service (RLS) protocol
Table 2-1. Information held by the HFDL aircraft and ground station sub-systems

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RF Basics, RF for Non-RF Engineers


Radio frequency (RF) can be a complex subject to navigate, but it does not have to be. If you are just getting started with radios or maybe you cannot find that old reference book about antenna aperture, this guide can help. It is intended to provide a basic understanding of RF technology, as well act as a quick reference for those who “know their stuff” but may be looking to brush up on that one niche term that they never quite understood. This document is also a useful reference for Maxim’s products and data sheets, an index to deeper analysis found in our application notes, and a general reference for all things RF.

The wireless radio technology that is so ubiquitous today is relatively new. However, there is a long and rich background that leads to our modern knowledge. The very first investigations of what we now call the RF spectrum came from early experiments in optics, electricity, and magnetism. The behavior...

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Performance Analyzing on Aviation Air-Ground Data Link

Abstract As the standard equipment of the commercial aircrafts, air-ground data link system is widely used in modern aviation transport. However, its validity was unsatisfactory in our testing, especially in error of transmission. In this paper, some influencing factors during air-ground data transmitting were analyzed from the signal transmission. Considering ACARS was based on ARINC-618 protocol, a fundamental study in this article on transmission signal and demodulating signal of the ground air data link system was done on the basis of ACARS signal generated by the transient aircrafts.


As the rapid development of the aviation industry, the modern air transport aircraft is becoming more and more digital. A large number of flight data and information can be collected through various methods and recorded. Through the air-ground data link, real-time data communication can be enabled while airplane is in flight. As a complement and extension of Flight Data Recorder (FDR), the air-ground data link can continuously transmit aircraft performance and navigation data in real time to...

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Case Study: EMTEQ uses Airtel ATN’s onsite test service to validate B767 Data Link and ACARS equipment


Founded in 1996, EMTEQ is a worldwide leader in the aviation industry. The company specialises in avionics systems and products for retrofit and forward fit applications. Customers include: airframe and avionics equipment OEMs, system integrators, modification centres, engineering and leasing companies and military subcontractors. EMTEQ has been contracted by Guggenheim Aviation Partners to manage the avionics modifications on three aircraft undergoing a passenger to cargo modification. EMTEQ is responsible for Data Link testing of the modified aircraft.

Enabling Technology

Airtel ATN’s onsite test service involves an Airtel ATN engineer who uses Airtel ATN’s MVDL portable test station. This is the only Data Link test station on site in Singapore and it can be operated as either an aircraft or a ground station.


The tests took place on the first of these 3 aircraft in Singapore on a Boeing 767 (B767-300ER) in October 2013. Airtel ATN’s on site testing helped identify connectivity issues with the local ground station. This meant that the system...

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