Aerospace & Defense
Advanced software for military telecommunications applications
Seven Solutions has a large expertise on the development of cutting-edge solutions such as local positioning systems for highly denied GNSS signal environments, highly reliability software, deterministic communication buses with integrated Radio over Ethernet and high-bandwidth data transfer, Space instrumentation or FPGA board for distributed radars. Find some use case examples below.
Radio-over-Ethernet (RoE)
Radio-over-Ethernet (RoE) allows the distribution of data and timing over networks. It is used for distributed telescopes, radars, ultrasound sensors and distributed communication emitters/receivers (cognitive radio systems, phased arrays,etc). It improves system performance, simplifies deploymentand reduces cost and cabling weight.
• Provide synchronization trigger signals to ADCs/DACs with an error better than 1 ns over areas of tens of meters up to several kilometers.
• Disseminate common frequency values with a phase-noise jitter below 1 ps in those areas, including temperature compensation mechanisms.
• Provide programmable frequencies, triggers or phase delay capabilities.
• Use flexible ring and/or start network topologies with high scalability (tens to thousands of end nodes) and several hops over up to 20 cascaded devices.
• Distribute data and commands within the same interface using standard Ethernet software tools.
• Provide interoperability with COTS devices based on Ethernet interfaces.
• Allow the utilization of networking configuration and monitoring tools.
• Provide failover mechanisms and timing error detection features.
• Integrate self-calibration capabilities for easy deployment and commissioning.
• On some applications, reduce cabling and its associated weight.
Audio and RF Intermediate Frequency VITA49 Recording Software
The Audio and FR Intermediate Frequency VITA49 Recording Software (IFRP-SW) is part of a Communication Electronic Support Measures (CESM) subsystem, contracted by INDRA.

Figure – Data and control interfaces of the recording/reproducing system
Main features:
– Composed of a digital signal recording system within a Commercial Off-The-Shelf (COTS) server
– Records Intermediate Frequency (IF) data, generated from monitoring receivers in wide and narrow bands
– Communications are carried out over 10 Gbps optical fiber links and 1Gbps Ethernet links.
– Records Digital audio from different hosts of the network
– Reproduces previously recorded digital audio and IF
– Different formats for IF data: raw, VITA49
– Audio reproduction using RTSP
– Development/Management tools: Jira, Git/SVN, EA, Visual Studio, Unit Testing, JMeter, Selenium, Jenkins and SonarQube.
Seven Solutions Quality Assurance Development
Highlights:
– Development framework based on a V life-cycle, following a Top-Down approach (from specifications to testing),
– Developed according to UNE-EN-ISO-9000, UNE-EN-ISO 900, PECAL 2110, PECAL 2210 and ISO/IEC 25010:2011.
– Quality assurance activities: Requirements capture and definition, analysis and functional design, architecture and technical design, coding and source control, testing and deployment plan, code quality.
– Continuous integration improving the traceability between requirements, design, implementation and integration.
The TSN Technology
Time-sensitive networking stands out against existing fieldbuses and Ethernet-like alternatives as it consists of a number of enhancements over regular Ethernet networks brought forward by the IEEE standardization committee (TSN Working Group).
This technology is designed along four main features:
a) The system-wide synchronization supplies a common network notion of time to synchronize the operation of the system nodes through a particularized implementation of the precision time protocol (PTP or IEEE-1588). This is known as gPTP timing and is described in the 802.1AS specification.
b) The bounded end-to-end latency can be guaranteed with the utilization of TSN traffic shapers such as the time-aware traffic shaper (TAS) defined in 802.1Qbv. Furthermore, delivery jitter can be reduced with the implementation of the frame preemption enhancement (802.1Qbu & 802.3br) of the Ethernet MAC.
c) The system-wide configuration and management is essential to leverage all the capabilities of TSN networks. As a rule of thumb, traffic identification rules for VLAN encapsulation (802.1Q) of TSN streams, routing and topology information, the activation of redundant paths, or GCL definitions have to be supplied.
This is usually achieved with resource reservation protocols such as 802.1Qcc or 802.1BA.
d) The redundant topology networks, which are often required in avionics networks, are also supported in TSN systems by following the 802.1CB recommendations. This allows the transmission of duplicate messages over different physical paths as an enhanced layer of protection for highly critical data following a very standard-based and cost-effective mechanims.

Figure – Development life-cycle and tools
Time Sensitive Networking (TSN):
Deterministic Ethernet
for next generation aerospace systems
The following case study shows an example of the expertise of the company in avionics systems, showing collaboration with GMV and PLD in the framework of different ESA projects. The goal is to develop a new candidate solution for time critical application busses, taking full advantage of the opportunity open for the ‘retiring’ of the MIL-BUS-1553 bus on this field.
Seven Solutions has developed a Deterministic GEthernet network bus. It is implemented as FPGA IPCORE compliant with the TSN standards but with very light footprint, making it suitable for resources and cost optimized applications. Powered by the utilization of the ESA RTEMS OS, this solution provide the first accurate implementation of a IEEE-1588 protocol profile for this OS, as well as a deterministic and best-effort bus solution with redundant topologies and resilience features.
This IPOCRE has been designed and developed by Seven Solutions upon system requirements and validation methods provided by GMV with a first use case identified on the MIURA 1 sounding rocket whose mission is to provide microgravity environment to payload experiments but also to provide a flying test bed for technologies that will fly with MIURA 5 micro launcher.
The 7S TSN Solution GETDEN: Light TSN for Avionics
The proposed system is based on a FPGA unit based on Xilinx Zynq family and based on low cost COTS elements with extended environmental range capabilities. A four ports Ethernet board has been designed and validated for vibration and temperature conditions. Exhaustive testing has been done to guarantee the highest reliability on the rocket communications including analysis of key failures and worst case application scenarios.
– N-Port TSN Switch Implementation with easy integration of additional IP modules on the FPGA.
– Four different traffic priorities with deterministic latency better than 1us (emitter-2 hops- receiver).
– Full support for TSN redundant streams.
– ESA RTEMS as system OS for easy integration on avionics systems. Ethernet and timing drivers provided and integrated into the Zynq architecture.
– System allows straightforward interfacing of non-TSN data streams (Sink/Source peripherals) onto the TSN network without requiring intervention from the OS software.
– Synchronization accuracy better than +/- 50 ns span.
– Decoupled, C99 & 802.1AS compliant User API
Scientific Space Instruments
Seven Solution has collaborated intensively in the design of space instruments for several Space missions. For instance, for the ESA Space missions and in collaboration with Andalusia Institute of Astrophysics (IAA).
Contributions
We have participated on the following missions/instruments:
Exomars, NOMAD instrument. Contribution: development of embedded OS drivers for RTEMS and LEON-3 architectures
Solar Orbiter, SO/PHI instrument. Contribution: FPGA IP cores (VHDL) and VIRTEX4 board design.
Sunrise 2009, IMAX instrument. Contribution: image processing DSP software (baremetal code) and FPGA IP cores.
