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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.


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.


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

where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
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.
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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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