High Performance Airborne Router for Critical Defense ISR

iDirect Government Technologies’ (iGT) new satellite airborne router, the e8000 AR, is for government customers who want high speed communications on a variety of transport and intelligence, surveillance and reconnaissance (ISR) aircraft platforms. The new router is designed for easy roll-on, roll-off integration into both low-speed and high-speed military airframes, supporting multiple missions from a single satellite router or modem that can be connected into an existing iGT regional or global satellite internet protocol (IP) network.

The e8000 AR is a software-defined satellite modem that comes in a one RU rack-mount enclosure, 21 inches deep, and fits into the smallest portable flyaway cases. Weighing less than 16 pounds, the new router will not bust the operator’s margin for weight. Also included are locking Ethernet, RF and 38-999 connectors that provide military-grade interfaces for high performance and secure connections that will not loosen during operations where high vibration is present. With both AC (100 to 240 V, 50 to 400 Hz) and DC (28 V) inputs (see Figure 1), the router can be easily powered from an airplane’s native power bus eliminating power converters that may produce dirty power. The entire unit is designed and tested to meet MIL-STD 810G airborne environmental standards and MIL-STD 461F standards for EMI and radiated emissions.

Figure 1

Figure 1 e8000 AR back side inputs and connections.

iGT routers have flown on multiple military airframes, from the low-speed King Air C12 surveillance aircraft to the high-speed C17 transport aircraft, supporting multiple military-specific applications. The e8000 AR router’s high-speed communications-on-the-move (COTM) features along with the iDirect IP network, delivers voice, video and data applications to and from personnel on board the aircraft. The e8000 AR can be optimized for downstream or upstream data rates using either Deterministic Time Division Multiple Access (D-TDMA) or Single Channel Per Carrier (SCPC) operational modes. The router can be operated in either mode and switched by the operator depending upon the mission. For bandwidth intensive ISR applications, the e8000 AR can be operated in SCPC mode where up to 19 Mbps can be transmitted off the aircraft in the upstream path. These data rates can support multiple high-definition cameras for surveillance and sensor data from on-board video and sensor gathering equipment. The e8000 AR can also be operated in D-TDMA mode for improved bandwidth efficiency and achieve transmit data rates as high as 11 Mbps upstream from the aircraft, depending upon satellite link budget limitations.

Router data rate performance on aircraft platforms are antenna and satellite frequency band dependent. The e8000 AR is designed to operate in any combination of antennas and satellite frequency bands, including wideband global satellite (WGS) constellation, to provide optimum performance to the operator. The e8000 AR has a built-in open antenna modem interface protocol (OpenAMIP) to interface with airborne antenna’s antenna control unit (ACU), which provides real-time location and pointing information during flight. For antennas without OpenAMIP, the e8000 AR includes an on-board CPU with an applications interface (API) for custom antenna interface development. The CPU comes with a thin-Linux operating environment that can be accessed through keyboard, video and mouse (KVM) interface, front-panel USB, or Ethernet port.

Some frequency bands, such as Ku-Band, have adjacent satellite interference (ASI) requirements due to decreased satellite spacing that can limit the power spectral density (PSD) transmitted from an airborne antenna system. The e8000 AR router has inherent COTM features that allow the operator to continue to optimize data rate performance, select operational modes and comply with ASI requirements. The router does this with spread spectrum technology that allows waveform spreading to meet PSD requirements, while maintaining the same data rate. The e8000 AR supports spreading factors 2, 4, 8 and 16.

On other satellite frequency bands such as X-Band and Ka-Band, ASI is less of an issue due to increased satellite spacing and allows much higher transmit power in the airborne antenna system. The e8000 AR takes advantage of this higher power operating environment and can be operated without waveform spreading, and uses SCPC mode where iDirect routers have achieved data rates upstream from the aircraft as much as 14 Mbps from a 17-inch airborne antenna.

The e8000 AR also supports COTM features such as automatic satellite beam switching (ABS) and global roaming. Airborne networks can be regional, multi-regional or global as airplanes typically travel great distances and it can require more than one satellite or satellite beam to cover the traversed area. In order to maintain constant communications when the antenna needs to re-point or the modem needs to select a new beam, the e8000 AR and iDirect’s Global Network Management System (GNMS) work together to make this physical transition nearly seamless. Along with on-board satellite beam maps, GPS input and an awareness of a multi-node network, the e8000 AR provides the intelligence to transmit when it is safe, or legal to do so, and switch between satellites as the airplane moves from one satellite beam or coverage area to another satellite beam, reestablishes the connection and provides the optimum data rates that can be achieved for that link.

In addition to delivering high performance, the e8000 AR is certified to federal information processing standard (FIPS) Level 2 and can be operated in transmission security (TRANSEC) mode while operating in an airborne network. The iDirect system uses AES 256-bit key encryption and exchanges X.509 digital certificate authentication with automatic key management. The e8000 AR can be operated with TRANSEC in a regional or global network with the use of iDirect’s unique global key distribution management system that allows roaming between secure networks.

The e8000 AR operates in a star topology and uses standards-based DVB-S2 with ACM waveform and can operate in networks with downstream rates up to 45 Msps and upstream rates up to 15 Msps in SCPC mode. Input frequency range is 950 to 2000 MHz and supports WGS frequencies. Modulation formats on the downstream are QPSK, 8 PSK and 16 APSK, and BPSK, QPSK and 8 PSK on the upstream.

iDirect Government Technologies,
Herndon, VA
(703) 648-8118,