Quadrature Phase Shift Keying (QPSK) is the digital modulation technique.Quadrature Phase Shift Keying (QPSK) is a form of Phase Shift Keying in which two bits are modulated at once, selecting one of four possible carrier phase shifts (0, Π/2, Π, and 3Π/2).
QPSK perform by changing the phase of the In-phase (I) carrier from 0° to 180° and the Quadrature-phase (Q) carrier between 90° and 270°. This is used to indicate the four states of a 2-bit binary code. Each state of these carriers is referred to as a Symbol.
Quadrature Phase-shift Keying (QPSK) is a widely used method of transferring digital data by changing or modulating the phase of a carrier signal. In QPSK digital data is represented by 4 points around a circle which correspond to 4 phases of the carrier signal. These points are called symbols. Fig 4.1 shows this mapping.
Fig: QPSK diagram showing how four different binary codes can be transmitted
Fig: Block diagram of a QPSK transmitter
In fig shows a block diagram of a typical QPSK transmitter. The unipolar binary message (data) first converted into a bipolar non-return-to-zero (NRZ) sequence using a unipolar to bipolar converter. The bit stream is then split into two bit streams I(in-phase) and Q(Quadrature) .The bit stream in-phase(I) is called the “even” stream and quadrature(Q) is called “Odd” stream.
The input data go to the Serial to Parallel Converter then it is split up into two. The two bit stream fed to the Low pass filter (LPF).Then the two bit stream after filtering fed to the modulator. The filter at the output of the modulator confines the power spectrum of the QPSK signal within the allocated band.The two modulator bit stream are summed and fed to the band pass filter (BPF) and produce the QPSK output.
QPSK is used extensively. Some of the popular applications of QPSK include:
- CDMA Systems
- Iridium(voice/data) Satellite Communication System
- Digital Video Broadcasting Satellite (DVB-S)
- QPSK is used for satellite transmission of MPEG-2 video
- Cable modems
- Videoconferencing
- Cellular phone systems and other forms of digital communication over an RF carrier.
- Applications of Filter Circuits
- Examples of Combinational Logic Circuits
- Calculating Voltage Drop Through a Resistor
- Waveform Generator
- Diode Clipper (Part 2)
- Zener Diode Specification (Part 2)
- Atom Energy Levels
- QPSK Theory
- Phase Shift Keying
- Schematic circuit for frequency modulation.
- What is Network Analysis?
- Series and Parallel Circuit Diagrams
- Band Pass Filters
- High Pass Digital Filter
- Branch Current Analysis
{ 92 comments… read them below or add one }
Thought I would comment and say superb theme, did you design it yourself? Really looks superb!
I really treasure this wonderful write up. I really appreciate the information you have provided in this article. Thanks a lot!
What PC games does the xbox 360 windows controller the job by? I recently signed up to a xbox controller for The PC, but do not know what computer game this functions via, or Techniques to To Use this.
I just added your web page to my favorites. I really enjoy reading your posts. Thank you!
Eventually, I proven the understanding I was searching out for. We have been holding out studying on this topic, and for four nights I protect acquiring web-sites which are meant to have what I am hunting for, only to get disappointed using the lack of what I wished. I wish I could have located your web sooner! I had about 25% of what I employed to become in require of and your web site has that, plus the remainder of what I essential to end my studying. We have now activated to this web site proper right here I like that you will discover authentic report written content that you’ll be in a position to hardly find out elsewhere. A single good matter, you perhaps can obtain nonetheless these sorts of information sites, ensure you go on! I can no lengthier see the preferred media. It can be there a good deal rubbish printed, I bear it no a lot a lot more quickly. A certainly pleasant web site and beneficial write-up. I spend nights inside of the world wide website studying blogs, about tons of many subjects. I ought to original of all give kudos to whoever established your websites and second of all to you for composing what i can only describe as an post. I honestly consider there is a capacity to writing content articles or weblog threads that only several posses and frankly you may have it. The combination of beneficial and excellent content material is totally exceedingly tight utilizing the enormous volume of web site round the online entire world.Often preserve a really very good give good benefits!
Concise and well written, ty for the post
I have been meaning to post something like this on my website and this gave me an idea. Thank you.
Is it okay to reference some of this on my site if I post a link back to this web page?
Hi there, This web site is really exciting and satisfaction to learn. I’m an enormous fan from the subject matter discussed. I also get pleasure from learning the reviews, but learn that alot of individuals ought to remain on composition to try and add worth in direction of the authentic weblog post. I would also encourage each and every person to save this web page to get a preferred assistance to help allocated the appearance.
The very simplest approach to get full laser hair treatment within driving distance has become word of mouth and not from an physician that is getting a piece of the pie. I used to visit an MD to get ipl treatments. I had spotty hairy areas and had already been thru the rest of the hair removal techniques. I bought the silk’n and have not been more pleased. Then finally I am hair free during the summer season time. This is going to be a splendid yr for me.
I just added this feed to my bookmarks. I enjoy reading your posts. Tyvm!
good article…
Straightforward and well written, ty for the post
I have wanted to write about something like this on my blog and this gave me an idea. Thank you.
Keep it up, wonderful job! Just the stuff I had to know.
I enjoyed reading this, a good fast read.
When I click your RSS feed it looks like a ton of weird text, is the problem on my side?
TY for blogging this, it was very informative and helped me tons
such a tough topic covered so well, great read. thanks for the post
There once was a cheapskate from Ramper, Who bought the smallest small camper, Said “I really love you,” “But there’s not room for two,” “You’ll have to go sleep in the hamper!”
Just thought I would comment and say great theme, did you make it on your own? Looks excellent!
Me too, tyvm for posting this..
Tyvm for the useful post! I would not have gotten this otherwise!
I just added this feed to my bookmarks. I really like reading your posts. Thank you!
Is it okay to reference some of this on my webpage if I include a backlink to this web page?
I just added this feed to my bookmarks. I really like reading your posts. Thanks!
Acquire every dose of Lexapro with a complete glass of water.
I will steered toward because me personally we give thanks stint you deplete knock croak the result. I’m egotistic furthermore flush unconnected allotment hang about for the supersede dojigger. Your article on the website is very interesting.
I’m having a strange issue I cannot make my reader pick up your feed, I’m using google reader fyi.
Thank you, nice post! Exactly the stuff I had to have.
True love is like ghosts, which everybody talks about and few have seen.
Is it alright to put some of this on my blog if I post a reference to this webpage?
Portals supply a way for enterprises to supply a steady seem and feel with entry management and procedures for multiple applications and databases, which otherwise would have been various entities altogether.
A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.
Cool entry cheers, a good quick read.
This is a topic near to my heart thanks, found you through Bing.
TYVM, great post! Exactly what I needed.
Me too, thanks for sharing this..
I enjoyed reading this, do you have a RSS feed ?
an xbox controller for the pc is very good
Klonopin may cause harm to an unborn baby, and may cause breathing or feeding problems in a newborn.
I’ve meant to write about something like this on my site and you gave me an idea. Thanks.
A miss is as good as a mr
I’ll inform all my friends about your very good note about article. We look through your custom term papers referring to topic. Hence, at this moment I have got research papers or custom write I asked for. Thanks!
I’m having a small problem I cannot subscribe your rss feed, I’m using google reader fyi.
nice post great illustration thanks for sharing.
I have not had a cigarette in 10 years. The most terrible part concerning giving up may be the very first week. Happily this stuff were short lived and things improved as time went on as a result of the e cigarettes. You should not give in. Just be strong and you may well be a non-smoker once and for all.
I am really excited to get comments from your blog, Thank you so much. I’ll be interested to hear how….
Is it alright to post some of this on my site if I include a backlink to this webpage?
I just added your feed to my bookmarks. I really enjoy reading your posts. Tyvm!
Soma can trigger aspect results that may possibly impair your pondering or reactions. Be cautious if you dr or do anything that requires you to be awake and notify.
I stumbled across your site, and think it’s fantastic, keep us posting
Ultimately, I established the knowledge I was searching out for. We’ve got been having out due diligence on this topic, and for four days I preserve getting web-sites which are intended to have what I’m hunting for, only to get disappointed utilizing the are lacking of what I wished. I wish I could have discovered your webpage sooner! I had about 25% of what I applied to become in will need of and your web page has that, plus the rest of what I crucial to end my researching. We’ve activated to this website proper here I like that you just will notice unique guide subject material that you will be in a position to hardly find out elsewhere. 1 excellent point, you possibly can obtain nevertheless these sorts of sites, ensure you go on! I can no more lengthy see the preferred media. It may be there a whole lot rubbish printed, I bear it no a lot far more easily. A certainly pleasant website and great write-up. I expend nights within the world broad web learning blogs, about tons of numerous subjects. I should original of all give kudos to whoever recognized your websites and second of all to you for composing what i can only describe as an post. I honestly think there’s a ability to writing articles or web site articles that only a couple of posses and frankly you may have it. The combination of helpful and exceptional content material is completely extremely scarce utilizing the substantial volume of web site throughout the online planet.Often preserve a very excellent give great benefits!
Impressive blog! Wonderful awareness about the subject. Unquestionably a fresh bookmark.
I’ve meant to post about something like this on my website and you have given me an idea. Thank you.
Just thought I would comment and say great theme, did you design it yourself? Looks awesome!
Hey there, great article, a colleague through the fashion business linked me to your web page. I was born and raised in Los Angeles California and have been earning a living within the industry for that majority of my life. One of my current projects is really a discussion board for the fashion marketplace. Thanks for the useful facts.
I just added this site to my favorites. I enjoy reading your posts. Tyvm!
I really enjoyed exploring your site. good resource … thanks for sharing
My boyfriend only started a new position ever so he’s not going how to find health insurance companies being regarding Other month. I offered how to assistance him pay as a Physician’s get in beforehand Then, rather he definitely refuses and says he doesn’t want To waste money (as this I believe is a misinterpret Because this’s to regard To his health, but it’s never likes I can compel him To accomplish anything). that’s why I eliminate the alternative as to seeing the doctor, ever so I beg you do not suggest this.
The single peaked at multitude 24 on the Billboard Sizzling one hundred graph or chart and number 2 on the Incredibly hot R&B/Hip-Hop Tracks graph or chart.
I smoked cigarettes for a long time and giving them up had been almost impossible. I tried the many stop smoking methods still not anything helped. Then I found the electronic cigarette. The e-cigarette utilizes a nicotine substance that is made out of just nicotine. Not any poisons at all. They’ve already honestly saved my life.
I have wanted to write about something like this on my blog and this gave me an idea. TY.
Straight to the point and well written, thanks for the info
I have wanted to post about something like this on my blog and this gave me an idea. Thank you.
Lookup portals like this 1 aggregate outcomes from numerous investigation engines into a single web page.
Soma can trigger side effects that may possibly impair your considering or reactions. Be cautious if you drive or do anything at all that needs you to be awake and inform.
Thanks for the information and i pray that all contestant will be in top performance
Just thought I would comment and say neat theme, did you design it on your own? Really looks great!
Always tries to write niche topic
Really happy to get this type of comment. Cheers
Thanks for subscribe to my feed
yeah i did it. thanks for your motivation
yeah i have
Hope you’ll regular here
Yeah i have. To subscribe rss feed click here
I’m having a little problem I can’t get my reader to pickup your feed, I’m using google reader by the way.
Man, talk about a fantastic post! I?ve stumbled across your blog a few times within the past, but I usually forgot to bookmark it. But not again! Thanks for posting the way you do, I genuinely appreciate seeing someone who actually has a viewpoint and isn?t really just bringing back up crap like nearly all other writers today. Keep it up!
I agree, ty for sharing this..
While trying to giving up smoking, I discovered the smokeless cigarette. The compare e cigarettes uses a nicotine material that is made up of simply nicotine. No toxic substances all that. They have literally saved my life. Getting rid of sucking in smelly smoke feels stupendous to me!
What’s the difference between Santa and Tiger Woods? Santa stops after three Ho’s.
Thanks for the great information! I would not have gotten this on my own!
huge journal you’ve retain
TY for the useful post! I would not have gotten this by myself!
Wow this takes me back. Do you have a RSS feed?
This is really nice post. Thanks for sharing.
I gain a lot of valuable insights from reading what is presented on this site. I hope this site stays updated because I look forward to learning much more.
TY for blogging this, it was unbelieveably informative and helped immensely
Thanks for the great info! I would never have found this otherwise!
When I view your RSS feed it throws up a whole lot of garbled text, is the malfunction on my end?
great stuff , this really helped me out…i bookmarked it for future reference , keep em’ coming !
I have been to this blog before yet this is just about the best articles yet. keep writing!