3 research outputs found
Instruction set extensions for software defined radio on a multithreaded processor
Software dened radios, which provide a programmable solu-tion for implementing the physical layer processing of multi-ple communication standards, are widely recognized as one of the most important new technologies for wireless com-munication systems. Emerging communication standards, however, require tremendous processing capabilities to per-form high-bandwidth physical-layer processing in real time. In this paper, we present instruction set extensions for sev-eral important communication algorithms including convo-lutional encoding, Viterbi decoding, turbo decoding, and Reed-Solomon encoding and decoding. The performance bene ts of these extensions are evaluated using a supercom-puter class vectorizing compiler and the Sandblaster low-power multithreaded processor for software dened radio. The proposed instruction set extensions provide signicant performance improvements, while maintaining a high degree of programmability. Categories and Subject Descriptors C.3 [Computer Systems Organization]: Special-purpose and Application-based Systems|Real-time and embedded sys
Reconfigurable architectures for the next generation of mobile device telecommunications systems
Mobile devices have become a dominant tool in our daily lives. Business and
personal usage has escalated tremendously since the emergence of smartphones
and tablets. The combination of powerful processing in mobile devices, such as
smartphones and the Internet, have established a new era for communications
systems. This has put further pressure on the performance and efficiency of
telecommunications systems in delivering the aspirations of users. Mobile device
users no longer want devices that merely perform phone calls and messaging.
Rather, they look for further interactive applications such as video streaming,
navigation and real time social interaction. Such applications require a new set of
hardware and standards. The WiFi (IEEE 802.11) standard has been at the forefront
of reliable and high-speed internet access telecommunications. This is due to its
high signal quality (quality of service) and speed (throughput). However, its limited
availability and short range highlights the need for further protocols, in particular
when far away from access points or base stations. This led to the emergence of 3G
followed by 4G and the upcoming 5G standard that, if fully realised, will provide
another dimension in “anywhere, anytime internet connectivity.” On the other
hand, the WiMAX (IEEE 802.16) standard promises to exceed the WiFi signal
coverage range. The coverage range could be extended to kilometres at least with a
better or similar WiFi signal level.
This thesis considers a dynamically reconfigurable architecture that is capable of
processing various modules within telecommunications systems. Forward error
correction, coder and navigation modules are deployed in a unified low power
communication platform. These modules have been selected since they are among
those with the highest demand in terms of processing power, strict processing time
or throughput. The modules are mainly realised within WiFi and WiMAX systems
in addition to global positioning systems (GPS). The idea behind the selection of
these modules is to investigate the possibility of designing an architecture capable
of processing various systems and dynamically reconfiguring between them. The
GPS system is a power-hungry application and, at the same time, it is not needed
all of the time. Hence, one key idea presented in this thesis is to effectively exploit
the dynamic reconfiguration capability so as to reconfigure the architecture (GPS)
when it is not needed in order to process another needed application or function
such as WiFi or WiMAX. This will allow lower energy consumption and the
optimum usage of the hardware available on the device.
This work investigates the major current coarse-grain reconfigurable architectures.
A novel multi-rate convolution encoder is then designed and realised as a
reconfigurable fabric. This demonstrates the ability to adapt the algorithms
involved to meet various requirements. A throughput of between 200 and 800
Mbps has been achieved for the rates 1/2 to 7/8, which is a great achievement for
the proposed novel architecture. A reconfigurable interleaver is designed as a
standalone fabric and on a dynamically reconfigurable processor. High throughputs
exceeding 90 Mbps are achieved for the various supported block sizes. The Reed
Solomon coder is the next challenging system to be designed into a dynamically
reconfigurable processor. A novel Galois Field multiplier is designed and
integrated into the developed Reed Solomon reconfigurable processor. As a result
of this work, throughputs of 200Mbps and 93Mbps respectively for RS encoding
and decoding are achieved. A GPS correlation module is also investigated in this
work. This is the main part of the GPS receiver responsible for continuously
tracking GPS satellites and extracting messages from them. The challenging aspect
of this part is its real-time nature and the associated critical time constraints. This
work resulted in a novel dynamically reconfigurable multi-channel GPS correlator
with up to 72 simultaneous channels.
This work is a contribution towards a global unified processing platform that is
capable of processing communication-related operations efficiently and
dynamically with minimum energy consumption