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This module contains the full compilation of testing results for the filter bank project.

Testing parameters

All data was collected on a laptop equipped with an AMD A6-3400M “Llano” quad-core processor which supports a clock rate of up to 2.3 GHz.

Test Parameters
Test Filter 4-pole Butterworth bandpass filter
Input channels 256
Time samples 600,000
Data filter cycles 100
Compiler GCC

The following results tables show the individual parameters of experiments, averaged run times of the program and an indicator of the real-time processing speed of the program (the formula to generate this figure is shown in the equation below).

F s N t = F s t N

where F s = sampling rate of incoming data (samples/sec), N = number of samples processed by filter bank (samples), and t = time to process all samples (sec).

Comparison of optimizations using compiler flags and intrinsics

Unique Filter Coefficients
Optimization Time (sec) secs/sec (25 KS/s)
None 619.940 0.25831
O3 Compiler 241.131 0.10047
O3 and SSE3 75.589 0.03150
O3 and our SSE3 69.258 0.02886
Constant Filter Coefficients
O3 and SSE3 55.835 0.02326
O3 and our SSE3 49.271 0.02053

Implementations of posix threads

4 tests under various PThread control conditions demonstrate similar patterns according to thenumber of PThreads used during code execution. Compiler Intrinsics : Implementation with naive data structures relying purely on compiler optimizations of SSE3 intrinsics Our Intrinsics : Implementation with naive data structures using our custom SSE3 intrinsics code Partial Reordering : Implementation assigning an output vector to each thread utilizing compiler intrinsics Full Reordering : Intermediate variables are aligned by channel and separated by thread
POSIX Threads
Optimization Time (sec) secs/sec (25 KS/s)
0 Threads and our SSE3 48.333 0.02014
1 Thread and our SSE3 50.109 0.02088
2 Threads and our SSE3 88.632 0.03693
4 Threads and our SSE3 138.090 0.05754
8 Threads and our SSE3 62.481 0.02603
16 Threads and our SSE3 103.901 0.04329
32 Threads and our SSE3 78.219 0.03259
0 Threads and SSE3 48.075 0.02003
1 Thread and SSE3 64.302 0.02679
2 Threads and SSE3 96.755 0.04031
4 Threads and SSE3 123.931 0.05164
8 Threads and SSE3 67.629 0.02818
16 Threads and SSE3 141.329 0.05889
32 Threads and SSE3 121.134 0.05047
Reordered Output Data
Optimization Time (sec) secs/sec (25 KS/s)
0 Threads and SSE3 50.106 0.02088
1 Thread and SSE3 49.302 0.02054
2 Threads and SSE3 78.888 0.02054
4 Threads and SSE3 89.939 0.03747
8 Threads and SSE3 35.283 0.01470
16 Threads and SSE3 71.337 0.02972
32 Threads and SSE3 109.112 0.04546
Reordered Intermediate Variables
0 Threads and SSE3 71.166 0.02965
1 Thread and SSE3 57.156 0.02382
2 Threads and SSE3 52.639 0.02193
4 Threads and SSE3 48.939 0.02039
8 Threads and SSE3 33.589 0.01400
16 Threads and SSE3 51.543 0.02148
32 Threads and SSE3 110.716 0.04613

Comparison of initial optimizations to posix thread implementation

Both tests show code execution times based on different methods of compiler optimization. Test 1 allowed for unique filter coefficients and test 2 had constant coefficients. Both tests used inefficient data arrangement.

Our optimal filter design incorporated a combination of several of the methods we used to optimize our filter bank implementation. It made use of compiler-level optimization, SSE instructions, and POSIX threads. It processed 60 million samples for each of the 256 channels in 33.589 seconds. Assuming a 25 KHz sampling rate, each second of of data is processed in 14 milliseconds (25 KS/s) and thus acceptable for real-time processing.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Efficient real-time filter design for recording multichannel neural activity. OpenStax CNX. Dec 11, 2012 Download for free at http://cnx.org/content/col11461/1.1
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