European Space Agency

Wideband-DSP System

Objectives

SIECAMS Wide Bandwidth Digital Signal Processing (SIECAMS WB-DSP) is planned to be a high-bandwidth, low cost signal analyzer front-end for the monitoring system SIECAMS which is used for analyzing and monitoring traffic transmitted via communication satellites. In order to meet the growing demand for monitoring high bandwidth transponders (Ka-band) and carriers the system will support the latest high end digitizer equipment in combination with a customized high-bandwidth direct conversion down converter to be controlled by SIECAMS.

SIECAMS is a COTS product which is in operation at several satellite and telecom operators. The SIECAMS BOX combines the entire SIECAMS monitoring software with a powerful DSP monitoring device in one single rack mount server.

The intention of this ARTES 3-4 project is to develop a wide-band DSP unit which represents a new SIECAMS BOX able to monitor satellite transponders up to 250MHz bandwidth. Several concepts applying different combinations of down-converter and digitizer equipment needs to be analyzed. Trade offs in terms of measurement dynamic (ADC vertical resolution) and acquisition time shall be discussed.

The following picture provides an example of the HW architecture of a standard SIECAMS BOX.


click for larger image

Challenges

  • Analysis of Different Concepts,
  • Investigation in Different Architecture,
  • Development of a new WB_DSP SIECAMS BOX,
  • Dual channel operation.

Benefits

The Key Benefits for the customer are:

  • 250MHz instantaneous bandwidth provides the possibility of monitoring ka-band transponders in one snapshot. No need to concatenate several measurements.
  • Detection and classification of carriers with an occupied bandwidth of up to 250MHz.
  • All the SIECAMS DSP functionalities like blind scanning or hidden carrier analysis can be applied.
  • European solution which would apply to the non-dependency initiative of the European Union.
  • Highly scalable and flexible –measurement devices can be easily added to increase the performance of the system -> reduces round robin measurement time of satellite traffic.
  • Cost effective – compared to DSP devices from R&S or Agilent, the SIECAMS BOX provides a fully integrated cost effective monitoring solution.

Features

The following picture provides an example of the HW architecture of the new WB DSP SIECAMS BOX. It consists of a rack mount server hosting the digitizer board as well as a direct conversion down converter unit.


click for larger image

The received L-Band signal will be amplified in the signal conditioner unit. The purpose of this unit is to adjust the amplification of the signal in a way to achieve the best operating point in terms of ADC resolution as well as not saturating the frequency conversion unit.

At the output of the direct conversion unit dedicated low-pass filters will take care that the Nyquist criteria is met. The cut-off frequency of these filters depends on the bandwidth requirement and the sampling rate of the digitizer which is planned to be 500 MS/s. Consequently, the filter cut-off frequency will be above 125 MHz in order to achieve 250 MHz instantaneous measurement bandwidth.

The proposed digitizer provides 2 channel input what offers to sample both I and Q channels with a single digitizer card (PCI Express) supporting a maximum theoretical signal bandwidth of 500 MHz which is reduced by applied Nyquist filters accordingly. The direct conversion down-converter with L-band input frequency range is planned to be selected during the project.

A first investigation turned out that several models from different manufacturers are available on the market, but only in terms of PCBs without any housing. Therefore, we intend to integrate the down-converter boards together with the signal conditioner in dedicated 1U rack mount housing.

Plan

For each phase of the development process a review is defined in order to verify the results of the phase concerning technical aspects, quality assurance aspects and project control aspects.

Current status

Acceptance test was performed. Preparation for the final review meeting on September 27, 2011.

Status date

Thursday, February 27, 2014 - 08:52