European Space Agency

Telco EGSE (Power & TMTC SCOE) - C&G-6A.069-Telco EGSE (Power & TMTC SCOE)



The overall function of the Atos Baseband TM/TC SCOE and TM/TC Crossbar is to provide validated interface hardware and software functions to interface baseband TM and TC hardware with the remaining EGSE infrastructure. This includes high-speed baseband data interfaces to On-Board Computers, COMMS elements such as Transponders and Modulators, Security Units, etc. Further applications of the envisaged functions are EGSE systems on subsystem level, which require baseband TM/TC interfaces and functions based on these, as well as Umbilical Test Systems used at the launch location, prior to connecting the actual spacecraft.

Telco EGSE Power SCOE:

The Power Special Check-Out Equipment (SCOE) is part of the electrical ground Support Equipment that provides via the current Atos UniverSAS® product the required electrical power, simulates the real spacecraft battery and the solar array behaviour and provides monitoring of some onboard electrical parameters. It is used during all phases of the spacecraft integration and test, i.e. from Avionics Test Bench (ATB) and Service Module (SVM) integration up to the launch campaign. The main objective is to extend the capabilities of the Atos UniverSAS® product to cover also different Telecom satellite requirements through generic firmware and software solutions.



  • Porting, partial re-implementation and extension of legacy Atos TM/TC Crossbar functions to different HW
  • Using a different way of reliable data transfers in a new HW/SW environment
  • Data rates and latencies at the lower level HW/SW layers and at the higher-level SW layers.

Telco EGSE Power SCOE:

  • Hardware/Firmware Layer development:
    • S3R support, including current slope behavior
    • Synchronization across multiple devices
    • Reduction of ripple and spikes for SAS, BS and BCE
  • Software Layer development:
    • SCOE application software to support the hardware/firmware enhancements
    • Support higher telemetry rates with a high number of power sections
    • Master/Slave configuration



  • Cost effective COTS HW elements and highly customizable SW layer
  • Support for SBDL/RS422 and LVDS electrical interfaces
  • Powerful and flexible interface between specific hardware and software layers
  • Broad range of EGSE functions can be supported
  • Support for more TM and TC baseband interfaces in parallel
  • Provision of a sync pulse for CADU ASM detection
  • Consistent and feature rich Software, conveniently adjustable for project needs
  • Support for various TM encodings (no-coding, convolutional, Reed- Solomon, Turbo codes, optionally LDPC) and rates
  • Local MMI, remote control by CCS
  • TM Transfer Frame to TM packet conversion
  • CLTU Analysis and Plausibility Check function
  • TM Simulation/generation function
  • Archiving of all TM/TC data, extraction/retrieval in human-readable format
  • External software interfaces supporting CCS/EDEN, NDIU, CFDP protocols

Telco EGSE Power SCOE:

  • Multiple UniverSAS®with Master/Slave functionality
  • The capability of having multiple UniverSAS®in parallel to address more than 18 kW
  • S3R and the maximum power point tracking (MPPT) ready and available in UniverSAS®hardware platform.
  • Hardware/firmware/software modifications and enhancements for Telecom Satellites AIT environment:
    • Battery simulator
    • Solar Array System
    • PCDU simulator
  • Higher power efficiency.
  • Less ripple and less spikes for SAS, BS and BCE.
  • Higher telemetry rates with a high number of power sections rate.



  • FPGA IP core for USB communication:

Allow reliable long-duration operation over the USB interface to the host computer at the required data rates and latencies

  • FPGA IP cores for the TM/TC Crossbar function

Cover all TM/TC Crossbar requirements as in the legacy implementation, extend the functions to support longer ASMs (e.g. needed for LDPC), raw bit-stream output, graceful handling of almost noise CLTUs

  • Flexible level convertors

Modular approach removing or reducing custom wiring and mechanical fixing

  • TM/TC-FE Service Interface

Migrate the lower levels of the software stack to USB communication. Extend the API functions to more parameter and functions.

  • TMTC SCOE Controller Software

Create the top-level TMTC SCOE Software, allowing TM and TC processing in various standard formats, display, routing, archiving and retrieval of data, support for external interfaces (e.g. CCS).

Telco EGSE Power SCOE:

  • UniverSAS® Master Slave Functionality

Allow operation of at least 32 SAS channels

  • Synchronisation across multiple UniverSAS®

Allow synchronisation of at least 32 SAS channels with a high resolution

  • Higher Telemetry Data Rate

The TM packets including data for at least 32 SAS channels in master and slave configuration have to be delivered in a cycle time of less than 500ms.

  • Sequential Switched Shunt Regulator (S3R) support

Handle S3R with a toggling frequency of up to 30kHz.

  • Constant current slope behaviour of UniverSAS®

Current slope dI/dU for output current between Isc and Imp shall be adjustable for a section with a range of 1/Rs from zero to 5% of Isc/Voc.

  • MPB Control loop enhancement for load operation

For generic load simulation inside a Payload Load Simulator (PLLS) the UniverSAS®Electronic Loads must also be capable to support the following modes:

Constant Current (CC), Constant Power (CP), Constant Resistance (CR).

  • SAS Ripple and Spikes

Ripple ≤ 150mVpp @ 20 MHz bandwidth while retaining a low output capacitance ≤ 250nF.

  • BS/BCE Ripple and Spikes

Ripple ≤ 50mVpp @ 20 MHz bandwidth

System Architecture

Telco EGSE TMTC SCOE - Architecture:

  • Hardware elements of the TM/TC Crossbar and TMTC SCOE
    • FPGA-based core hardware
    • external computer for monitoring, control and data processing
    • level convertor hardware that adapts to the desired external logic levels
    • mechanical envelope
    • internal electrical harness
  • Software layers of the TMTC SCOE
    • TM/TC Crossbar data exchange layer
    • TM/TC encoding/decoding layer with filtering possibility
    • TM reception, TM generation and simulation layers
    • TC generation, TC reception layers
    • TM/TC Transfer Frame and Packet Archive and extraction tool
    • local MMI, centralized logging mechanism
    • external interfaces (CCS, NDIU, etc.)

Telco EGSE Power SCOE – Architecture:

A significant part of the enhancement development will focus to improve UniverSAS® with the requirements of Telco Satellites. The most important areas are indicated in orange in above figure.

  • Hardware enhancements
    • Synchronization across multiple UniverSAS®
    • Modification of output buck converter filter stage for sufficient ripple and spike reduction
  • Firmware enhancements
    • Support HW enhancements in project scope
    • Fast S3R transient support by improved control loop and PWM logic
    • Improving of control loop and PWM logic for constant-current slope
    • Implementation of Constant Current (CC), Constant Power (CP), Constant Resistance (CR) simulation for enhanced load simulation functionality
  • Software enhancements
    • Support for HW and FPGA enhancements in project scope
    • Inter-UniverSAS®synchronization interfaces, GUI and CCS remote control interfaces for providing of Master/Slave functionality
    • Optimization of telemetry generation for faster telemetry rates


High Level Project Plan with milestones

WP1000 PM / QM

KO: Kick-off Meeting PM / QM Activity

WP2000 Requirements Analysis

WP2100/WP2200 TMTC/POWER Requirements Analysis WP3000 Design

WP3100/WP3200 TMTC/POWER Design

MS#1: Critical Design Review (CDR) WP4000 Implementation

WP4100/WP4200 TMTC/POWER Implementation WP5000 Manufacturing

WP5100 TMTC Manufacturing

WP6000 - Integration, Verification and Validation WP6100 TMTC Integration and Verification

MS#2: TMTC/POWER - Test Readiness Review (TRR)

TMTC/POWER - System Test + Factory Acceptance Test (FAT)

MS#3: TMTC/POWER - Test Review Board (TRB)

WP6200 Power Integration and Verification

WP7000 Final Report

MS#4: Final Settlement

Current status

Project Kick-Off done and the HW/SW technical requirement specification and preparation for the requirement review milestone ongoing. The requirement documentation is currently in review at ESA.

Status date

Tuesday, July 7, 2020 - 12:01