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Students are to implement and optimize a power spectral density estimator, a pseudo-noise (PN) sequence generator, and an IIR filter.

In this lab you are to implement and optimize the a pseudo-noise (PN)sequence generator, IIR filter, and autocorrelation routines that are part of the previous lab's PSD estimator.For the lab grade, you will be judged on the execution time of your system (memory usage need not be minimized).

Reference implementation

After taking a look at the source code of the PSD estimator reference implementation, youwill likely discover inefficiencies. This implementation is provided as the "reference implementation" of the optimization process and todefine the expected input and output of the application. The computational efficiency of your code will be judged against this implementation.While the given code might serve as a starting point, you should do whatever you need to do to make your code as efficientas possible, while operating in an equivalent manner as the given code.

The exact portion of the code to be optimized is defined below. You may write in C, assembly, or any combination of the two; choosewhatever will allow you to write the fastest code. The optimization process will be smoother if you plan for optimization beforeyou begin any programming.

Optimization

Since a primary purpose of this lab is to learn optimization and efficient code techniques, your lab grade will be based primarily on the total execution time of your system. You are not required to optimize memory use. Note that by execution time we mean cycle count, not the number of instructions inyour program. Remember that several of the TMS320C54xx instructions take more than one cycle. The multicycleinstructions are primarily the multi-word instructions, including instructions that take immediates, like stm , and instructions using direct addressing of memory (such as ld *(temp),A ). Branch and repeat statements also require several cycles to execute.Most C instructions take more than one cycle. The debugger can be used to determine the exact number of cycles used byyour code; ask your TA to demonstrate. However, since the number of execution cycles used by an instruction is usuallydetermined by the number of words in its encoding, the easiest way to estimate the number of cycles used by yourcode is to count the number of instruction words in the .lst file or the disassembly window in the debugger.

We will grade you based on the number of cycles used between the input_full = 0; and bit_rev_fft(); statements. Note that some instructions, like RPT , are non-repeatable instructions ; their use may cause unnecessary glitches in I/O. For grading simplicity, your finalcode should not have modifications except between these two instructions, and M should be set to 31 . If the number of cycles between the two points is variable, the maximumpossible number of cycles will be counted. You must use the core.asm file in v:\ece320\54x\dsplib\core.asm or the C core file in v:\ece320\54x\dspclib\core.asm as provided by the TAs; these files may not be modified . We reserve the right to test your code by modifying the inputs.

Routine-specific optimization tips

If you are programming the PN generator in assembly, you may wish to refer to the description of assembly instructions forlogical operations in Section 2-2 of the C54x Mnemonic Instruction Set reference. Initialize the shift register to one. You can debug the PN output bycomparing it to the output of the MATLAB code. Be prepared to prove to a TA that your PN generator works properly as part of your quiz.

Your IIR filtering routine can debugged by writing an impulse followed by zeros in autocorr_in instead of randsample .

Your autocorrelation routine can be debugged by commenting out the IIR-filtering routine and writing the maximum DC value into autocorr_in in a similar manner as described the IIR-debugging step. Note that each of these tips is the most helpful ifthe output is inspected in memory.

Grading

This lab is to be completed in one week. Grading for this lab will be a bit different from past labs:

  • 1 point: Prelab
  • 2 points: Working code, implemented from scratch in assembly language or C.
  • 5 points: Optimization. These points will be assigned based on your cycle counts and the optimizations you have made.
  • 2 points: Oral quiz.

Questions & Answers

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
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
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.
Bharti
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
Daniel
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
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
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
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
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.
Tarell
what is the actual application of fullerenes nowadays?
Damian
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.
Tarell
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.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Digital signal processing laboratory (ece 420). OpenStax CNX. Sep 27, 2006 Download for free at http://cnx.org/content/col10236/1.14
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