The objective in this Artes-3 project was to develop frequency generating modules to EQM level. Four different Local Oscillator Modules were defined, ranging from 20MHz to 2.4GHz. The 20MHz LO was designed as a high resolution synthesiser, while all the other EQMs are SPLO designs using SAW resonators in the VCO. These designs exhibit excellent phase noise performance.
Norspace AS believes that increased R&D efforts within the frequency generation area can open the need for a family of Local Oscillator Modules that will fit in with company strategic needs.
The proposed program took advantage of the results already achieved in the finalized FGU project (Artes-3) and explored similar but more advanced architectures to extend both the frequency span of this design and make the design more flexible.
The key issues in the development have been to design frequency generating equipment and demonstrate Norspace's capability in this field. The developed designs are focused on low phase noise. By selecting a modular approach, flexible and adjustable designs are developed.
The development will strengthen the competitive position for Norspace with respect to new multimedia market satellites. This program is a part of the strategy to establish a product portfolio within the frequency generating equipment.
The program has given an overall risk reduction with respect to technology issues and cost issues for commercial programs involving frequency generating modules. Through the development Norspace has gained improved knowledge of different build technologies and elements, thus improving the capability to meet challenging requirements in commercial projects.
Four different EQMs have been developed. Three of them have further explored the benefits and possibilities of the SPLO design in the S-band, L-band and UHF band respectively. All of them use SAW resonators in the VCO loop. The fourth EQM is based on a digital synthesizer for selection of high resolution frequencies in the (V)HF band.
The SPLO architecture combined with the SAW resonator based VCO has demonstrated a very low phase noise. In particular, SAW resonator implementation in combination with a low frequency (typically 10MHz) reference source generates a wide variety of frequencies with 10MHz spacing. The program has expanded the frequency range for the SPLO design. One EQM at 2.4GHz is derived from the 10MHz reference. To make this architecture even more flexible, this program has demonstrated methods which improve the resolution of the selected output frequency. This is demonstrated by the L-band and UHF band LO modules.
The usefulness of the SPLO is increased by the design of a flexible, high resolution synthesizer in the (V)HF range. This module can be used alone or in combination with the SPLO. In this case the SPLO will provide a fixed frequency with low phase noise, then, by mixing this frequency with the flexible synthesizer, a high resolution output frequency can be obtained.
The project was redefined with a CCN and new project plan was defined. There have been three main milestones in the project; BDR (Baseline Design Review), MTR (Mid Term Review) and FR (Final Review).
T1 = Contract Change Notice (Program Redirection) Kick Off
System Studies & Trade Off Analysis
The first phase leading up to BDR and consist of the following tasks:
- System optimisation and Building Block Specification
- Technology Evaluation
- Test Definition
Equipment Design and Development / Test Development
The second phase ends at MTR and includes:
- Module overall design
- Detailed design
- Qualification of parts, materials and processes
- Test Development
EQM Assembly Integration and Test
The last phase ends at FR and includes:
- EQM1-4 assembly and verification
- Equipment EQM Assembly and integration
- Equipment Test and reports
The program is completed. The EQM models have been tested and verified through a test campaign. The results show excellent performance and the EQMs are compliant to all major requirements in the target specification.