# Lab 5: optimization theory

 Page 1 / 2
An overview of DSP optimization techniques, from the design stage, through high-level implementations, to assembly implementations.

## Introduction to code optimization

Most practical DSP applications have a clock-cycle and/or memory budget. Initial implementations typically don't meet these budgets;therefore, the code must be optimized. Code development usually follows six steps:

• Develop algorithm on paper
• Simulate in MATLAB
• Develop and simulate more efficient implementations
• Implement algorithm in C
• Use library routines when available
• Use optimizing compiler
• Manually write assembly routines for key routines

## Develop algorithm on paper

The algorithm to be implemented should first be designed on paper. In addition to equations describing the algorithm, its design shouldinclude inputs and outputs of each routine and a flow chart of the operation of the complete program. Never design an algorithm or a program at a computer. While it may be possible to implement some basic algorithms and programs this way, compilers cannot overcome any designflaws that are likely to be introduced.

## Simulate in matlab

Before any C code is written, the algorithm should be developed and simulated in MATLAB since problems with the algorithm design can befound more easily. This is done by applying the algorithm to test vectors and inspecting and/or plotting the results. Once thealgorithm is completely defined, C implementation can begin. Recall that in each of the previous labs a MATLAB simulation step was givenbefore assembly implementation.

## Develop and simulate more efficient implementations

An efficient algorithm used as few multiplications and additions as possible. Applying DSP theory to "simplify" the algorithm is a commonway of doing this. The autocorrelation function is a simple example: a simple-minded way of implementing this is tocompute sums for each lag, but careful inspection of the autocorrelation function reveals that it is actually a function of the absolute value of the lag. Therefore each value at a negative lag is identical to the value at the correspondingpositive lag. Approximately half the apparent multiplications and additions aretherefore required. If the entire autocorrelation sequence is needed, the autocorrelation can be optimized even furtherif it is treated as a convolution of two sequences. An FFT and an inverse FFT can then be used to compute the autocorrelation.

## C implementation

After the algorithm has been designed and optimized, an initial implentation in C is done. Tips on writing code with efficiency inmind can be found here . It is important, however, to get a working implementation ofthe algorithm in a reasonable amount of time as some optimizations cannot be anticipated by the programmer.Some of these coding techniques in the URL reference can be applied later on when it is clear which routines need the most optimization.This implementation can serve as a reference implementation to compare the correctness and speed of optimized versions.

how to know photocatalytic properties of tio2 nanoparticles...what to do now
it is a goid question and i want to know the answer as well
Maciej
Do somebody tell me a best nano engineering book for beginners?
what is fullerene does it is used to make bukky balls
are you nano engineer ?
s.
what is the Synthesis, properties,and applications of carbon nano chemistry
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
so some one know about replacing silicon atom with phosphorous in semiconductors device?
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 ?
for screen printed electrodes ?
SUYASH
What is lattice structure?
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
what's the easiest and fastest way to the synthesize AgNP?
China
Cied
types of nano material
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
what is nano technology
what is system testing?
preparation of nanomaterial
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
what is system testing
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
how did you get the value of 2000N.What calculations are needed to arrive at it
Privacy Information Security Software Version 1.1a
Good
Berger describes sociologists as concerned with
Got questions? Join the online conversation and get instant answers!