Uranus

Objectives

The objective of this activity is the definition and development of a universal integrated 4 watt Ku-band transceiver (DRU5), which will be compliant with SatLab specifications. This new product (transceiver) will offer important new functions, which are currently not provided by any competing product or company:


  • Fully integrated single Universal LNB, enabling full DVB-S overlay for DBS applications and the most flexible transponder planning,

  • Possibility of dual polarity (cross polar and co polar).
Skyware Radio Systems has already developed a "1st generation" Ku band transceiver for satellite interactive terminals. Whilst this design represents a considerable cost reduction over more traditionally designed transceivers, significant opportunities for further cost reduction and performance enhancement remain. It is the purpose of this project to address these opportunities, leading to a fully integrated and more flexible product, ready for full industrialization.

As with the current Skyware satellite transceivers, this 2nd generation product will be a fully integrated unit, designed for low cost manufacturing technology, similar to those used in the manufacture of DVB-S type of Ku-LNB's.

Challenges

The one box design approach is demanding in terms of tooling and tolerances, but also rewarding as it results in an easy to assemble and compact product, which is easy to handle and install.

A serious effort was needed for the assessment of the tolerance sensitivity of the casted-in waveguide filter resonators. Skyware has extensive experience of handling die-casting tolerances. For example, it has been proven that with good quality die-cast tooling the repeat tolerance of critical dimensions is far less than absolute dimensional tolerance. During the filter design work packages this experience is of great value.

In a normal LNBF, the LNA inputs are connected to a simple and compact OMT-WG transition structure. The inputs of the URANUS LNA however, are connected to two different waveguides which are located at different places in the product. The x-polar input is connected to a TRF WG-filter, while the co-polar input is connected to a relatively large WG-diplexer filter elsewhere in the product. This requires a much bigger PCB which is more difficult to integrate into the concept.

Next to this essential design constraint, the RF screening of this new LNA and mixer deck is much more critical compared to a TVRO single. This requires much more carefully RF screening as many other strong sources of RF energy are present in a very small volume.

Benefits

It is the purpose of this product is to address new Ku commercial opportunities, The new product design will lead to wider access to interactive satellite services due to improved performance and reduced BoM & manufacturing costs.

Given that most of the commercial opportunities thus far are targeted at business market, the ease of installation of a single unit as well as the size become even more important.

For the first time a DVB-RCS outdoor unit will be able to accommodate broadband applications as well as broadcast applications in the same unit.

Features

The transceiver will be the radio module of a Ku Two Way Satellite System. The transceiver will be designed to be compatible with:


  1. Market available Ku Band reflectors/feedhorns and

  2. Modems (IDUs)

The DRU5 Ku-band transceiver series incorporates the traditional ODU components: transmitter (BUC), a receiver (LNB), and OMT /diplexer into a single mechanical structure. This required the following 3 board designs: RX Board, TX Board, CAPSU Board.







To the right is a high level overview
of the key submodules of the unit.  As can be seen in the figure, the Uranus transceiver
features two LNB input paths for the corresponding orthogonal input polarizations. This enables cross-polar as well as co-polar TX-RX operation which will enable global sales.

 


click for larger image


Plan

The design project has now been completed and five mechanical samples have been built and tested. All units are within the specification. The next enhancements to the product will be for higher powers and for a higher stability LNB.

Current status

Many technical challenges were overcome during the development of the radio. Some of the key technical achievements of the project are listed below.


  • A thermo-mechanical platform has been developed capable of dissipating 42W of power whilst maintaining the electrical components within reliable operating conditions at ambient temperatures of 55ºC.

  • A compact integrated OMT / Diplexer has been developed and manufactured using volume manufacturing processes. The assembly provides well matched ports for transmit and dual selectable receive polarisations, whilst also providing the high level of filtering required for transmit and receive signals.

  • The transmitter is capable of achieving either standard, 14-14.5GHz or extended 13.75-14.25GHz by selection of PLDRO and microstrip filters.

  • An integrated transmitter has been developed which is capable of generating 2W, 4W or 6W output powers.

  • Remote control / telemetry function via the TX IF cable is possible using the DiSEqC protocol. The hardware has been included as optional components on the transmitter PCB and CAPSU PCB.

  • Five prototype radios have been successfully built and fully tested.
There is market requirement for high stability versions of the LNB, with local oscillator frequency as low as ± 3 ppm. The dual polarisation LNB developed for ?Uranus? will be modified to meet this requirement.

There is market requirement for higher power transmitter, with several applications requiring P-1dB of >/= 6W at P-1dB. Work will continue to further develop the 3 way splitter / combiner for combining the output PA MMICs

Contacts

Status date

Wednesday, June 18, 2008 - 18:05