MIMO channel Matrix decomposition

mimo channel matrix

Dear friends,

I am new in the field of MIMO Communications,I request you to please brief me about Singular Value Decomposition of Channel matrix H, I mean that what do the resultant unitary matrices and Eigen value matrix show in terms of communication.

Please recommend me some resources where I can learn Matrix theory involved in MIMO Communications.

Waiting anxiously for your reply.

Robert

parallel decomposition of the mimo channel

Hi,

First of all about yur question related SVD, I have already wrote the detail ansewer of this question on the forum, you can easily find it on Digital communication section.

In brief, svd is used to decompose the MIMO channel into its parallel SISO channels, but a care should be taken while using svd that bcz it requries co-operation at the receiver end to receive the correct data and in most of the cases co-operation among receivers is not possible in mobile environment, so svd may not be a good choice in cellular systems. But you can use svd in point to point MIMO link where co-operation among receivers can be done easily. Second you can alos use QR decomposition in MIMO communication as well.

When u do svd, the eigen values are representing the channel gain of each single channel, unitary matrices are used for precoding the decoding the signal in order to reduce interference aong transmitted signal.

There is a very good articel by Arigyasawami Paulraj, a very well reputed and a big guy in the field of space time communicatin, Prof. from Stanford uni, the title of the articel is "MIMO Wireless Communications" its in some IEEE Trans. on Communication (if i m not worng) 2005. just google it and you will find.

There are couple of very good books, I always recommed if some one is interested in MIMO communication, the effectiveness of the books is in order as i m writing down, thats of course my understanding about MIMO stuff, and u may disagree with it. The Books are

1. Introduction to space time wireless communications by Arogyasawami Paulraj et al.

2. Wireless communications by Andrea Goldsmith

3. Fundamentals of wireless communications by David Tse and P. Viswanath.

The first two professors are from Satnford and David Tse is from UC Berkley.

1st book is an excellent text on MIMO stuff, and I advise you to follow the papers from paulraj and Goldsmith.

I hope I am helpful to you.

BR,

Arif Khan

Please press helped me !!!

mimo channel matrix

Dear friend,

Thank you very much for your response, dear I need your further help in sharing your views on the topic of MIMO Communications I want your advice that what field in MIMO I should select for my PhD studies, as I see from my perspective some future in area of "Cooperative MIMO Relaying" I don't know weather I am right or wrong so please share your views on this issue,and dear I could not find the article "MIMO Wireless Communications" but there is a book on the site with this title, if you have this than please share it and Finally dear in which situation do we use QR decomposition and in which situations do we use SVD.
Could you please recommend me some recent work in ""Cooperative MIMO Relaying" I mean some PhD thesis or Institute working in this area or some basic paper or tutorial.

Wishing you very best of Luck.

channel matrix(mimo)

Hi,

You can find the article i mentioned in my previous email from tis link.
h**p://niles.stanford.edu/~mhv/SPM_MIMO_Wireless_Precoding.pdf

To be very frank you asked too many things in one email, which i really want to answer in a bit detail, but not now may be in next week.

As for as I know about svd and QR decomposition, you can use both decompositions in MIMO communication but when you do svd, you get [U,S,V] matrices and S is a diagonal matrix and U and V are unitary matrices such that U*S*V gives you the original channel matrix back. But problem is that you get S and then multiply input vector to V and on the receiver side when you are decoding the message, you need the information of U which was done at transmitter and you need to kow the U of your neighbouring all recivers as well, which is very difficult to get in mobile environment. Further details on this topic you can find in the above mentioned article.

QR decomposiotn can be done at the transmitter and it does not need the additional info at receiver.

I would recommend you that go to matlab prompt and type
>>help svd
>>help qr

You will get detail explanation of these two methods.
Second source is the Linear Algebra book by MIT Prof. Gilbert Strang, an excellent text on LA and beautiful written book.

I will talk on Co-operative MIMO topic next time, hopefully.

By the way where you doing your PhD and where u from?

BR,

Arif Khan