In the STOLO project a prototype local oscillator was developed, based on spintronics. By using a spin torque oscillator instead of classical technologies NanOsc introduces a disruptive technology that is bound to change satellite communication devices in the future.
The first goal of the project was to create models for the component that can be utilized in industry standard electronic design tools. This will allow for the design of complex systems where the STO is just one of many components.
The second goal was to manufacture a system that can have an acceptable output for practical use. This will be accomplished by state of the art electronics design and by tweaking of different inherent properties of the STO.
Before the project, there was no available model of the STO for incorporation into more advanced electronics simulation packages (such as Cadence). This was a major limitation, which this project managed to solve.
Secondly the signal output of the bare STO was too small to be of practical use. This was be addressed both trough classical amplifier designs and by clever use of the inherent properties of the STO itself.
A contemporary oscillator design that is utilized in a satellite can weigh as much as 12 kg. With NanOsc nanotech based oscillator the weight could be just a fraction of that. The oscillator will be very well suited to space since it is inherently radiation hard. Due to its negligible size and weight, it will also fit well with future strategies such as “nano” satellites.
In our system there are three specific parts, a D/A converter for current control of the STO, the STO itself and the LNAs that will amplify the high frequency signal of the STO.
The projected was divided up in two phases. In Phase I, basic simulation tools were developed and basic experimental demonstrations were be carried out. This lead to a feasibility analysis and a go/no-go decision at BDR.
In Phase II, more complete simulation tools were developed and a full RF characterization of the STOs was carried out. Control circuits and LNAs were designed and combined with a PLL to get good output power and precise control of the STO.
The fully assembled system was then tested for performance.
The STOLO project concluded that the main benefit of the single un-synchronized STO is not to have it function as a stable high quality oscillator. However, our studies suggest that both line width and output power are improved by synchronizing several STOs. Thus more innovation on a basic device level is needed to utilize the STO in satellite communication.
New applications may be found for frequency generation in the high GHz range with a very large bandwidth. It is likely that the frequency of operation can be extended above 60GHz. We are currently looking in to this type of utilization for the STO.
Our view is that the STO could be utilised in the generation of microwaves up to the THz range for atmospherical observations or other applications.