ALLISS
Rotatable shortwave antenna system with solid radiators for international broadcasting.
ALLISS is a rotatable antenna system used for high-power shortwave radio broadcasting, operating in the 6 MHz to 26 MHz range. Each ALLISS module functions as a self-contained shortwave relay station for international broadcasting. The system is a special variant of the HRS type antenna, distinguished by its solid horizontal radiating elements, unlike the tensioned flexible radiators found in other HRS designs. The name combines the French towns Allouis and Issoudun.
True ALLISS technology is defined solely by these solid radiators; other rotatable HRS antennas, including some designs from Thales acquired through corporate purchases, are not considered genuine ALLISS. Of all HRS antennas in global use, only about 12% are rotatable, and among those, only 28 systems feature solid radiators. Roughly 20% of rotatable HRS antennas are ALLISS, though this figure may be slightly overstated. The Chinese SARFT is believed to operate replicated ALLISS modules, meaning Thales no longer holds exclusive control over the technology. Information about ALLISS may also appear under the names Ampegon, Thales Group, or Thomson-CSF.
Due to its high cost and complexity, ALLISS is not a consumer product. Cheaper alternatives exist for shortwave broadcasting. As a rule, ALLISS should only be purchased when 360-degree coverage is necessary. It is used exclusively by well-funded broadcasters and telecommunications operations that plan to operate the modules over their 50-to-60-year design lifespan. Each module costs around US$10 million, with some rumored to reach US$15 million; the four module versions can vary by as much as US$5 million. At least 30% of the cost stems from exotic metallurgy and metalworking requirements, placing ALLISS out of reach for many developing nations and even some advanced ones.
ALLISS allows broadcasters to change transmission parameters at any time: direction (azimuths from 0 to 360 degrees at roughly 1 degree per 6 seconds), broadcast frequency, and antenna configuration (e.g., HR 4/4/1 to HR 6/4/1). These changes can take effect in as little as 5 minutes, enabling a broadcaster to redirect an entire shortwave network to a strategic target within about 15 minutes.
ALLISS offers several advantages over traditional shortwave relay stations.
- Frequency range
- 6 MHz to 26 MHz
- Number of modules sold since 1989
- 32
- Estimated percentage of rotatable hrs an
- about 20%
- Number of alliss systems with solid radi
- 28
- Cost per module
- around US$10 million (some modules rumored up to US$15 million)
- Design lifespan
- 50–60 years
- Rotation rate
- ~1 degree per 6 seconds
Lore & Background
ALLISS technology emerged from a special design case of HRS type antennas, with the key differentiator being solid radiators. The name combines the towns Allouis and Issoudun in France. True ALLISS systems are distinct from other rotatable HRS antennas, though some pseudo-ALLISS designs have been procured through corporate acquisitions by Thales. Only about 12% of all HRS antennas in use globally are rotatable, and of those, only 28 systems have solid radiators. The Chinese SARFT is said to have replicated ALLISS module technology, meaning the technology is no longer exclusively in the domain of Thales.
ALLISS modules are self-contained shortwave relay stations that allow broadcasters to change direction (0 to 360 degrees), frequency, and antenna configuration in as little as 5 minutes. A broadcaster can redirect an entire transmission network to a strategically important target area in as little as 15 minutes. The modules are fully automated, requiring only a three-person support staff for several scattered modules, visited monthly for maintenance. This contrasts with conventional HRS relay stations, which require much larger staffs.
Versions of ALLISS modules have been installed in France (Issoudun and Allouis, 1995), Germany (Nauen, 1997), Oman (A'Seela, 2002), China (Qiqihar, 2003), Turkey (Emirler, before 2006), Kuwait (Sulaibiya, 2009), and Nigeria (Abuja-Lugbe, 2009). A contract for replication in Cuba was reported in 2009, but no construction evidence has been found. The total number of modules sold since 1989 is 32.
Reader's Guide
ALLISS technology represents a significant but niche approach to shortwave broadcasting, primarily due to its cost and complexity. With modules costing around US$10 million (and some rumored up to US$15 million), and at least 30% of that cost tied to exotic metallurgy and metalworking, the system is out of reach for most consumers and many developing nations. It is only used by well-funded broadcasting and telecommunications operations that intend to use the modules over their design lifespan of 50–60 years.
The modular construction allows relay stations to be built module by module, with each module able to start broadcasting as soon as construction is completed. ALLISS systems offer higher RFI and EMF compatibility compared to traditional relay stations. However, the technology's expense and complexity mean that cheaper solutions exist for shortwave broadcasting. As a rule of thumb, ALLISS systems should only be purchased if 360 degrees of coverage is necessary. The system's ability to change direction, frequency, and antenna configuration rapidly makes it strategically valuable for redirecting broadcasts to target areas. Despite its advantages, few broadcasters have geographically scattered modules for security and RFI reasons, partly due to poor understanding of the technology.
Did You Know?
- The name ALLISS is a concatenation of the French towns Allouis and Issoudun.
- Only about 28 ALLISS systems worldwide have solid radiators, distinguishing them from other rotatable HRS antennas.
- ALLISS modules can change broadcast direction, frequency, and antenna configuration in as little as 5 minutes.
- At least 30% of the cost of each ALLISS module is related to exotic metallurgy and metalworking requirements.
Frequently Asked Questions
What is ALLISS?
ALLISS is a rotatable shortwave antenna system built specifically for high-power international broadcasting. It covers the 6 to 26 MHz band, and each individual module operates as a fully self-contained relay station.
How does ALLISS differ from other HRS antennas?
The defining feature is its solid horizontal radiating elements, whereas most other HRS designs rely on tensioned flexible radiators. This solid-radiator construction is what separates true ALLISS from the broader family of rotatable HRS antennas.
Where does the name ALLISS come from?
It is a blend of two French towns, Allouis and Issoudun, which are tied to the system's development history.
How much does an ALLISS module cost?
A single module runs roughly ten million US dollars, though some units have been rumored to reach fifteen million. Since 1989 only 32 modules have been sold, with 28 confirmed as carrying the solid-radiator design.
What is the expected service life of an ALLISS system?
The design lifespan is in the range of 50 to 60 years, reflecting the heavy-duty engineering behind the solid radiators.
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