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Intellectual property speculation

While millions of people all over the world are chatting on their mobile phones, downloading music or watching streaming video on laptop computers, developers at Xilinx in Scotland are quietly working away in the background to make the underlying technology work – thinking up the “logic” which makes very similar chips do very different jobs…

Intellectual property speculation

“We provide solutions for many things consumers take for granted or depend on,” says Dr Colin Carruthers, Director, Xilinx Scotland. “We also do a lot of things that people aren’t even aware of, as they go about their everyday lives.”Sometimes, Xilinx thinks up new ideas which no-one has thought of before, and for which there may not even be a market yet… 

As far as the consumer is concerned, what Xilinx develops in Scotland is often invisible – blocks of logic which provide the intelligence for the FPGAs (Field Programmable Gate Arrays) used in many digital products.  The same FPGAs can be put into very different devices, but what makes them different is how they are programmed.  According to Carruthers, Xilinx chips are even used in the Mars Rover and particle accelerators to solve the greatest mysteries in science, as well as more common applications such as HDTV, mobile phones, PDAs and wireless basestations.

Xilinx customers can change or upgrade (i.e programme) product features and functions “on the fly” – adapting to new standards and reconfiguring the hardware for a specific application. This “on the fly” technology can be achieved even after the product has been installed in the field, allowing upgrades and design flaw repairs following consumer purchase.

Xilinx in Scotland

Xilinx today is the world’s largest maker of FPGAs,  with just over 50 per cent market share, and its  presence in Scotland can be traced back to a  company called Algotronix, a spin-out from the  University of Edinburgh in 1989 which became a  part of Xilinx four years later. Like Xilinx, which was  formed in 1984, the small team of developers at  Algotronix recognised the potential of FPGAs and  developed a numeric co-processor chip which fitted  in well with the Xilinx portfolio, plus several other  patented devices with commercial potential. Xilinx  also recognised the talent at the fledgling Scottish  company, and persuaded them to join forces – in  the process setting up the company’s first overseas  development venture, which has since become a  major European R&D centre for Xilinx. 

As the years went by and FPGA technology continued  to evolve, Xilinx in Scotland grew from four to 16  people, focusing on chip design and layout software,  as well as board level and development tools.  Now more than 40 strong, the Edinburgh-based  development team was not only able to take full  advantage of the company’s international marketing  strengths but also its software development skills,  documentation and chip verification capabilities – plus  what Carruthers calls “cross fertilisation of cultures.” 

In 1997, Xilinx had four or five radically different  FPGA platforms, all performing different tasks but  using very similar technology, so the company  decided to rationalise to avoid duplication of effort,  in the search for a more homogenous architecture.  At this time, says Carruthers, using FPGAs for digital  signal processing (DSP) was gaining momentum,  and this presented Xilinx with tremendous  opportunities, especially in the mobile phone market.

The next generation of the so-called  third generation “3G” wireless standard  is called Long-Term Evolution (LTE).  This provides a leap in performance  over existing standards, and presents  significant challenges to deal with  higher data throughput ratesTo meet the demands of the new  specification, Xilinx Scotland has  developed several new or revised DSP  LogiCORE(tm) solutions. With such  blocks, it is critical not only to verify  them as stand-alone blocks, but also  to validate them in real systems with  real-world data. The Xilinx LTE downlink  reference design was developed to  provide this validation, as well as  providing a reference to customers  about how to use the blocks. 

The LTE standard is still changing and  has not been ratified, making FPGA an  ideal implementation platform. The  design team decided to implement an  LTE reference system design that would  provide system level validation of the  new LTE LogiCORE IP using real-world  data sources such as video streams.  Since the main aim of the reference  system was to validate new IP LogiCORE  solutions, the team wanted to minimise  the amount of additional design work for  the reference design. They also wanted  to minimise the system integration and  tool issues and use off-the-shelf boards  and IP blocks as much as possible. 

The new solution was demonstrated  during February 2008 at Mobile World  Congress MWC08 in Barcelona,  with multiple video channels being  transmitted using the LTE encoding  and decoding.

By using existing Xilinx IP blocks to  maximise IP reuse, and using Xilinx  Platform Studio as a single integration  framework, design teams can  concentrate on the novel parts of the  LTE downlink design. This has allowed  rapid development and tracking of  changes in the LTE specification as it  approaches ratificationIn Scotland, the development  team focused on cores – blocks  of pre-coded functionality, to  which the customers can add what  Carruthers calls their “secret sauce”,  taking advantage of the reusability  of the components which sit on  the FPGA. The cores can even be  downloaded free from the web so  that customers can try them out  before placing an order. 

The Xilinx team in Scotland also works  very closely with Xilinx headquarters  to help in the design of new FPGAs,  and because they know the layout  of the FPGAs inside-out from the  moment they first hit the market, they  can quickly exploit the architecture  of the new chip design to optimise  results for different customers.  Although developers in Edinburgh  are pushing the edge of research,  Carruthers says they’re not engaged  in what is sometimes described as  “blue sky” thinking but very down to  earth and practical solutions for their  customers. In fact, their greatest  satisfaction comes from solving  real-world customer problems, as  well as dreaming up original ideas.  When the Xilinx sales team is talking  to customers, the Edinburgh team are  often called in for discussions, to talk  engineer to engineer, in order to come  up with new solutions. 

In terms of applications, Xilinx  solutions are used all over the digital  world. For example, it produces cores  which enable the FPGAs to be used in  mobile phone network base stations,  as well as the “satellite” base stations  which are now installed in buildings  to boost network signals. 
Paraphrasing the words of Arthur C.  Clarke, Carruthers says that Xilinx  technology is “sometimes so advanced  it’s hard to distinguish from magic”,  but its success in Scotland  is not an illusion.

What are FPGAs?

When they were invented, Field  Programmable Gate Arrays (FPGAs)  were regarded as an “off-the-wall  concept” that would never take off in  the market. Dreamed up by Xilinx  co-founder Ross Freeman, the  FPGA was a totally new kind of  semiconductor which could be  customised by individual customers  to meet special system requirements,  with the help of special software.  In the early days, however, the  technology required a lot of expensive  transistors, so many mainstream  companies rejected it because it did  not seem to be commercially viable. 

Thanks to Moore’s Law, which states  that the number of transistors you can  fit onto an integrated circuit doubles  every 18-24 months, enabling dramatic  reductions in costs, the Xilinx concept  soon became increasingly attractive  as a business proposition, and a  multi-billion dollar market has  emerged, providing smart solutions  for a wide range of industries and  applications – many of them hardly  imagined when the FPGA was  conceived. 

In simple terms, an FPGA is built  around a matrix of configurable  logic blocks (CLBs) connected via  programmable interconnects. Unlike  Application Specific Integrated Circuits  (ASICs), which are specially built to  carry out specific tasks, the same  FPGA can be programmed to do  different jobs, using the same  infrastructure laid out on the chip.  This means that the customer can buy  a lot of FPGAs off the shelf and then  configure them to carry out particular  functions, instead of building an ASIC  from scratch. As well as being much  more flexible and cost-effective, the  FPGA eliminates much of the blood,  sweat and tears that go into designing  new products. 


"Intellectual property speculation". Science Scotland (Issue Seven)
Printed from on 03/04/20 10:45:10 AM

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