LTE, WIMAX, MIMO, MATLAB

• ### Motorola’s 4TXx8RX LTE eNB May be the...

Since my last post I have been surfing the Internet looking for a commercial LTE basestation that would satisfy the bandwidth-hungry applications such as HD video conferencing and HD video streaming. Motorola seems to be the only company that has gone beyond the minimum requirements defined by...
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• ### 64% of Mobile Internet traffic will consist of...

As a follow up on my two previous posts I would like to share this important information: 64% of Mobile Internet traffic will consist of video. This was mentioned in a report produced by the Institute of the Future. Despite the fact that the report was commissioned by Skype, a major player in the...
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• ### Welcome to the real world!

I have just read two recent articles that every operator should pay attention to. The first one discusses the lower-than-expected download speed that a typical user terminal experienced, i.e. 5Mbps versus the 40Mbps advertised speed. This is not surprising given that the speed depends very much on...
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• ### User experience will ultimately decide the fate...

It is ultimately the user experience that will make or break mass adoption of 4G technologies such as LTE and WiMax. The end user does not really care what kind of PHY layer, MAC layer or network protocols these technologies use. The end user needs to be able to surf the Internet reliably, to...
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• ### Useful tips for completing your Ph. D. on time

Many people I know found it surprising that I was able to finish my Ph. D. within the normal four-year period. I do not blame them for that. After all the Arar inquiry was still going on. Back then I still had all the extreme pressure that came with the media attention not to mention [...]
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## Motorola’s 4TXx8RX LTE eNB May be the Solution

Nov 27th

Posted by Maher Arar in LTE

No comments

Since my last post I have been surfing the Internet looking for a commercial LTE basestation that would satisfy the bandwidth-hungry applications such as HD video conferencing and HD video streaming. Motorola seems to be the only company that has gone beyond the minimum requirements defined by 3GPP release 8. It is indeed a smart move.

More specifically they are now offering a basestation that can transmit with up to 4 antennas and receive on 8 antennas. While this falls short of what is needed Motorola seems to be on right track. I would not be surprised if we soon see an offering with up to 12 or more antennas on the receive side.

Bravo to Motorola for this kind of forward thinking

## 64% of Mobile Internet traffic will consist of video

May 21st

Posted by Maher Arar in Business

No comments

As a follow up on my two previous posts I would like to share this important information: 64% of Mobile Internet traffic will consist of video. This was mentioned in a report produced by the Institute of the Future.

Despite the fact that the report was commissioned by Skype, a major player in the personal video conferencing market, the arguments and numbers presented in the report make perfect sense. What backs this claim is the forcast made by Cisco that video will account for 91% of Internet traffic by the year 2013. No wonder why Cisco recently acquired Tandem for \$3 billion.

Because HQ and HD video traffic require a consistent high bandwidth (> 500 kbps), wireless operators will be faced with a dilemma: loose money or sacrifice QoS.

The ONLY way for wireless operators to avoid this dilemma is to increase the cell capacity beyond what is minimally required by 4G standards. The use of MU-MIMO (multi-user MIMO) will be a must. What this means is that operators have to seriously think about installing basestations with high number of antennas. As of today’s date there is no commercial basestation with more than 4 antennas.

This represents a business opportunity for a young wireless start-up. The key to success is to target very high number of antennas so that a sufficient increase in cell capacity is achieved. A BS with 16 antennas will provide a 4x increase in cell capacity compared to the one that has only 2 antennas (i.e. simultaneously serving 8 users versus serving only 2 users, respectively, assuming that each user has two anntenas).

## Welcome to the real world!

Jan 22nd

Posted by Maher Arar in Business

No comments

I have just read two recent articles that every operator should pay attention to. The first one discusses the lower-than-expected download speed that a typical user terminal experienced, i.e. 5Mbps versus the 40Mbps advertised speed. This is not surprising given that the speed depends very much on many factors including distance from the basestation, the number of active users in the cell, intra-cell interference, etc.

The second article discusses the fact that the lack of a proper scheduling algorithm that is suitable for 4G may hinder the expected performance and consequently user experience. This demonstrates that we still have a long way to go before we can have a reliable 4G network. My fear is that in their rush to compete for market share operators may end up doing more harm than good when it comes to promoting the use of their newly installed 4G mobile network. If the end user has a bad taste for 4G repairing the damage may not be possible.

## User experience will ultimately decide the fate of 4G

Jan 4th

Posted by Maher Arar in Business

4 comments

It is ultimately the user experience that will make or break mass adoption of 4G technologies such as LTE and WiMax. The end user does not really care what kind of PHY layer, MAC layer or network protocols these technologies use.

The end user needs to be able to surf the Internet reliably, to stream audio and video efficiently while paying the lowest price possible. The promotional headlines highlighting the fact that 4G will provide 100Mbps data rates is of no meaning to most consumers.

In my opinion, providing a reliable network access for HD video streaming, HD live TV and two-way HD video conferencing will be the main challenge for operators as the demand for these services is on the rise while compression technologies have reached their theoretical limits.

For 4G to be a success operators have to meet the above consumers’ expectations while managing to make an acceptable ROI.  Despite the bandwidth efficiency of OFDMA, as is used in LTE and WiMax, making money will be a huge challenge if QoS needs to be maintained at an acceptable level. This is because a substantial percentage of subscribers in a typical cell will either be streaming HD video or will be having a two-way HD videoconferencing session.

For the technical folks out there, let us remember that the advertised 100Mbps rate is a peak over-the-air data rate. What that means is that the average user will experience much less effective rates. This is fine if the majority of users are only surfing or talking, both of which are either bursty in nature (i.e. surfing) or requires very low data rate (i.e. voice) .

Will beyond-4G technologies such as LTE-advanced will be the answer? Only time will tell.

## Useful tips for completing your Ph. D. on time

Dec 31st

Posted by Maher Arar in Personal

1 comment

Many people I know found it surprising that I was able to finish my Ph. D. within the normal four-year period. I do not blame them for that. After all the Arar inquiry was still going on. Back then I still had all the extreme pressure that came with the media attention not to mention that my post traumatic stress level was at its peak. Coordinating my supporters’ and lawyers’ efforts was another huge task.

While luck may have played a role (like some people would like to believe) I am convinced that the following tips have allowed me, and I am sure will allow any future Ph. D. candidate, to finish on time:

## 1. Choose a research subject that you are passionate about

Before I even applied for admission I knew exactly what research area I was interested in. Choosing a topic that you are passionate about is crucial as it will help you keep the motivation levels high despite all the obstacles that you may face.

In my case, I found that the use of MIMO (i.e. multiple antennas at both the transmit and receive ends) to boost data rates without the need to use extra spectrum was an intriguing subject that was worth investigating.

## 2. Make sure your research topic has practical applications if not now but will in few years from now

This is important in the sense that your research should not be purely theoretical. This in turn will help you in your mission and keep you focused on your goal. Why? because you can feel the importance of what you are doing by simply reading business publications and by surfing the internet.

In my case I was able to easily find out that MIMO was going to be hot in WLAN and future 3G/4G as spectrum scarcity was on the rise and its acquisition cost was becoming more and more prohibitive.

## 3. Make sure you have a plan

Every Ph. D. candidate seems to agree that this is the most important thing they should be doing and yet I was amazed how many Ph.D. candidates I met did not have any plan at all. Knowing my research subject before I even took courses not only helped me choose the right ones but it also helped me choose the right topics for my term papers.

I was able to use not only the knowledge gained from writing these term papers but also many of the actual sections, figures, illustrations, etc. This will save you alot of time later when it is time to write your thesis. Never underestimate the time it takes to a produce a quality thesis.

## 4. Set achievable quarterly milestones

When it comes to measuring your productivity do it in quarters. With the help of your supervisor implement a milestone system by which you can either celebrate the outcome (and hence boost your motivation levels) or hold your self accountable for what went wrong. Make sure these milestones are reasonably achievable.

## 5. Build relationship of trust with your supervisor

You have to keep your supervisor as happy as you can and never play tricks with him/her. Try as much as you can to meet the deadlines for the milestones you and him/her have agreed to.

In my case, I was able to meet most of the deadlines to the point where I was reminding him about them. That helped both of us build the required trust that normally lacks in many student/supervisor relationships. If you do this you will find that your supervisor will be your best ally.

Voila I have just shared with you my secret of how I was able to finish my Ph. D. in a record time given all the circumstances mentioned above.  Now let me go and celebrate this milestone of being able to write a blog post and share useful information with the rest of the world.

And the by the way, happy new year!!!!

## Ph. D. presentation slides

Dec 17th

Posted by Maher Arar in MIMO

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In case you are interested:

Presentation Thesis

## Today I successfully defended my Ph. D. thesis

Dec 16th

Posted by Maher Arar in MIMO

9 comments

Congrats to me! I can finally say that I am a Dr. or may be Dr.2 to be more precise (because of my honorary Ph.D. degree from Nipissing University). It was an extremely tough year. I had to work more than full time (you figure out what that means) to be able to finish by the end of the year.

My supervisor asked me what is next and I told him that I have a lot of thoughts (not plans!) about what to do next. I do not want to think about it now. It is time to enjoy and celebrate this achievement. I will certainly make up my mind by early 2010.

If you ever think of embarking on a Ph. D. adventure at the University of Ottawa you may find the following presentation inspiring enough! Enjoy watching.

## Why did I decide to start blogging?

Dec 14th

Posted by Maher Arar in Personal

1 comment

I have been wondering for a while whether I should jump on the Web 2.0 wagon and join the rest of the world. It was not an easy decision to make. After all I have always valued my privacy and have always preferred to keep my opinions to myself.

I have finally surrendered as I have become convinced that my life will never be private again.  Also, we live in a constant surveillance society any way and the BIG BROTHER is watching 24/7. Time will tell if the decision I took this week is the correct one.
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