RF Engines Ltd (RFEL), the specialists in innovative
signal processing design, has developed a new range of
Fractional Resampling Architectures for FPGA that can be
used to perform up-sampling or down-sampling of high-speed
digital signals. The designs are based on a unique
architecture that offers significantly greater user
flexibility in the design of the resampling filter and
better dynamic range, when compared to designs based on
traditional architectures. The design is also
unrivalled in its ability to efficiently handle thousands
of channels simultaneously and independently.
Fractional resampling is a signal processing function
that enables the manipulation of the signal sample rate, so
that it may be precisely matched to the requirements of
subsequent processing. This has many applications,
but RF Engines designs are particularly relevant for
matching symbol and sample rates in digital receivers,
enabling the modulators and demodulators to be
significantly simpler and cheaper. Examples include
telecommunications modulators and demodulators, image and
video processing, audio processing, and interfacing to
hardware components with fixed sample rates.
John Summers, RF Engines’ VP of Sales and
Marketing commented, “The fractional resampler
cores are the latest addition to our range of high
performance signal processing building blocks. The
new cores achieve industry leading performance and
flexibility. They provide designers with much greater
freedom in their system design and the ability to do all
this with low risk and to a shortened timescale. In
addition, and perhaps most importantly, they can help to
achieve significantly reduced overall system design
costs.”
The RF Engines architecture is highly scalable, and has
a unique benefit in that it can support resampling of just
one channel or thousands of channels simultaneously, whilst
maintaining efficient use of silicon resources, and
providing excellent filtering performance in order to
mitigate the effects of aliasing. The resampling
rates can be selected with high precision, and allow
selection of output sample rates with a resolution less
than one Hertz. When operating on multiple input
channels, the architectures treat each channel
independently, allowing different input sampling rates, and
rate changes for each channel. Furthermore, the rate
change required for each channel can be updated at runtime,
without affecting the operation of other
channels.
The IP designs are provided as an EDIF netlist for
either Xilinx or Altera FPGA devices, and are custom
generated for each specific requirement to ensure a minimal
FPGA footprint, and the lowest power consumption. As
with all RF Engines cores, the Fractional Resamplers are
supported by bit-true Matlab models, allowing early
validation of the core through simulation, and thereby
reducing risk.

RF Engines’ resampler cores lead the industry for
performance and flexibility
An example core for the Xilinx Virtex II Pro 50 FPGA is
able to down-sample 512 channels simultaneously and
independently. The core supports maximum input
channel sample rates up to 25 MS/s and a maximum aggregate
sample rate for all channels combined of up to 280
MS/s. Each channel can be down sampled by a
user-selectable factor of up to one hundred with a
sub-Hertz frequency resolution. This particular core
requires approximately 10% of the resources on the Pro
50.
RF Engines
RF Engines Limited (RFEL) is a UK based designer,
providing high specification signal processing cores,
system on chip designs, and FPGA based board solutions for
applications in the defence, communications and
instrumentation markets. These applications include
base stations, wireless and wireline broadband
communications systems, satellite communications systems,
test and measurement instrumentation, as well as defence
systems. More specifically, RFEL is a solutions
provider for projects requiring complex front end, real
time, wide and narrow band, flexible channelisation.
RFEL provides a range of standard cores covering multiple
FFT and unique PFT techniques, as well as system design
services for specialist applications.
For further information, please see the website at
www.rfel.com or contact RF Engines
at Innovation Centre, St Cross Business Park, Newport,
Isle of Wight, PO30 5WB, Great Britain. Tel +44 (0) 1983
550330. E-mail info@rfel.com
Press information and illustrations can be obtained from
Nigel Robson, Vortex PR, Island House, Forest Road,
Guernsey, GY8 0AB, Great Britain. Tel +44 (0) 1481 233080.
E-mail nigel@vortexpr.com