Space Solar Power!?

A couple of months ago I read an article on engadget about the Japanese plan to acquire solar energy from an orbiting satellite. The plan is to start by powering just a heater and then eventually get up to a system that could provide 1 Gigawatt of power by 2015. I personally believe this plan is over-ambitious, but as solar technology improves and rockets to launch satellites becomes cheaper, it might be feasible.

I can hardly fathom how many solar cells it would take to generate 1 GW of power. In my recent experience building an autonomous, solar powered vehicle for the IEEE Southeastcon 2010 Hardware Competition I did a lot of research on the capabilities of solar cells. Granted, we were only working with a solar array that provided a maximum of 2 Watts of power on a bright sunny day (inside of earths atmosphere). If today’s solar technology were used in this Japanese project, it would take approximately 1 million of the solar arrays that were used in my project, which would take up a space of a 167,000 yard x 167,000 yard square… imagine launching something that large into space.

So let’s say that the solar array is built… How much rocket power would it take to launch that gigantic array into space? I don’t really want to think about the weight of a structure that massive or how much rocket fuel it would take to get the thing into orbit. But I suppose it could be done. Once the array is in space, power then must be transmitted back to earth for it to be useful. The Japanese plan on using the 2.4Ghz band to send really powerful waves back to earth. That introduces a whole host of other problems.

Just imagine how much interference a 1 GW signal would introduce into any nearby cordless phones or remote control cars. I bet a young kid would be surprised if his toy car just started driving on its own. Another big issue is the danger of such a powerful signal to anyone that would come in contact with it. I’m sure that there would be a designated location for all of this power to be beamed back down to, but what if someone programmed the wrong bit into the navigation and aiming program of this satellite. I would imagine that 1 GW of microwaves could completely bake a human brain. Along the same lines, if this signal were definitely harmful to humans, why not use it as a weapon? A satellite might take some time to orbit over to another location, but it could potentially have a very wide range of aim and could be used to target very specific locations.

So this solar power from space sounds great in theory, but it is definitely a huge endeavor that has many obvious problems and introduces many different safety concerns. However, if the Japanese find a solid solution to this problem, space solar power could be a very profitable solution to energy needs. I don’t know the difference in deployment cost of solar satellites versus building a nuclear reactor or other power plant, but solar energy would generate very little waste and would not need fuel to operate (other than the rocket fuel to get it into orbit). Maybe the Japanese will be incredibly successful and there will be large scale space solar power all around the world… or maybe they will realize that launching an array large enough to provide significant power is a little unrealistic. We will just have to wait and see.

2010
04/25
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4G? Not really…

In my first post, we took a brief look at the history of cellular networks and some specifics of 3G. Sprint recently announced that they will be offering 4G networks. But in reality, there is no such thing as a 4G network yet.

The 4G standard is formally known as the International Mobile Telecommunications Advanced (IMTA) standard by the International Telecommunications Union Radiocommunication Sector (ITU-R). That’s a long, fancy name for “better, faster, and more reliable than 3G”.

The biggest change between 3G and [the future] 4G is that 4G moves to an all IP-switched network and the goal is to provide approximately 10x higher data rates for all users. This will be achieved by basically bypassing existing cell phone networks and achieving a fully mobile broadband (exactly like the FCC plan for rural broadband). There are two main groups that are working toward meeting the IMTA standard. Those groups are IEEE with Wimax (802.16e) and LTE with the LTE-Advanced (LTE-A) protocol. However, neither of the two groups have hardware that is up to par with the official 4G standard.

So far, I would say that IEEE is in the lead because WiMax is the standard used by Sprint and Sprint is the only wireless provider in the United States that is advertising 4G at this point. That is not to say that LTE-A is not doing comparatively well though. From the specs I have seen, WiMax is at a 56 Mbits/s uplink with a 100 Mbits/s downlink to LTE-A’s 50 Mbit/s up and 100 Mbits/s down. I sincerely doubt anyone can physically tell the difference in +/- 6 Mbit/s up speeds. But LTE says that their newest standard is not even scheduled to be released until 2011, which means that there is not likely to be any equipment that meets the standards until then (by the way, Verizon and AT&T claim that they will be using the LTE standard). Regardless, neither competitor is anywhere near the nominal 1 Gbit/s (only when the device is not moving) speeds that the 4G standard is pushing for.

Why would you call a network 4G if it doesn’t yet meet the standards by the main organization over telecommunications? Mostly because the majority of consumers don’t really care that much about standards. In fact, most consumers probably won’t even read the fine print at the bottom of the Sprint 4G page that clearly states “up to 10x faster claim: based on download speed comparison of 3G’s 600 kbps vs. 4G’s 6 Mbps. Typical published 3G average speeds (600 kbps-1.7Mbps); 4G average speeds (3-6 Mbps).”. I think we can all do the math on that.

As with everything I have discussed, there are several more details about the 4G standard that could be covered. But they are all more technical items about data transmission schemes, advanced network protocols, antenna configuration, etc that very few people care to read about. Basically, today’s “4G” as advertised by Sprint is not up to par with the standard defined by the ITU. We will just have to wait and see how long it takes IEEE and LTE to get everything up to speed or if the official standard will be changed based on what can actually be done with today’s technology

2010
04/23
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Androids Everywhere!

So, I promised you all a post on the Android OS. As I’m sure most of you know, the Android Operating System is Google’s smart phone OS. Unlike, the iPhone OS, Android is EVERYWHERE and the software development environment is very friendly. Not to mention, the app store is open to anyone who wants to write an app and there are no restrictions placed on what compilers may be used.

I’m going to start with the software side of things since I have actually had some experience writing applications for Android. The first day that I sat down to learn how to write applications it took me about 4 hours to get the dev kit set up. This was a little bit annoying, but I blame it on the Windows distribution of Eclipse (I was at work) since it took me less than an hour to set up the dev kit on my Macboook. Anyway, the recommended development environment consists of Eclipse, the android SDK, and a plug-in that is download from google (how convenient) to put it all together. Once I got everything up and running it only took me about 20 minutes to get a “Hello World!” application running on the Android simulator that comes with the dev kit.

The thing that I think makes the Android development environment so nice is that all Java classes are allowed. Thanks to UAB, I know Java. In addition to the already powerful Java library, Google provides developers with some very useful and convenient bonus classes. For example, say you wanted to write a GPS app. Guess what, there is a command to initialize the Google Maps interface. Then you might want to say “find my current location”. That takes one line of code that says getCurrentLocation(). I’m sure you can imagine creative things to do from there.

Another very cool and easy to use bonus class of the Android OS is the textToSpeech class. When I was at the SoutheastCon 2010 Software Competition last month, we were challenged to write 7 applications in a day. One of them required taking text as user input and making the phone read it back to the user. It took me and my teammates about 45 minutes to write that app. Thanks for making things so easy Google.

In addition to having a great development environment, there are a whole lot of phones that run Android. So if you write an app for Android, it is available from the app store on not only the Google Nexus One, but on phones from several other manufacturers (HTC, T-Mobile, Samsung, Motorola, Sony Ericsson, and a couple more). So unlike the iPhone, you get several choices for the device that runs the operating system. Which is really nice because once you’ve chosen your phone OS you have the option to choose from several different form factors. I, for one, hate that fact that the iPhone doesn’t have a hard keyboard. Some people don’t mind so much. But if you like the Android operating system you can pick whether you have a real keyboard or touchscreen only. More options are always better.

As far as cell phone market domination goes, I think Google has set themselves up for a huge success. Android is lightweight, great to program for, and widely available. Google might not beat out Windows Mobile, or RIM, but I certainly think that Android OS will soon be more widely used than the iPhone OS. The future of Android devices looks promising and I certainly look forward to seeing how well Google can do in this market.

2010
04/23
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Broadband for Everyone?

Next up: the FCC. These guys are the big cheese of wireless communications in the United States. If it were not for them, we would probably have our airwaves polluted with amateurs invading the AM/FM waves, people broadcasting personal television stations, and who knows what else. In any event, the latest big endeavor for the FCC is their goal to provide high speed internet access (AKA Broadband) to everyone in the United States. Fortunately, most of us in the States already have a decent broadband connection, but the FCC claims that there are still 100 million unfortunate souls without high speed internet access. So the main purpose of Broadband Everywhere is to provide those people with a speedy, reliable connection.

Now since you probably already have a high speed internet connection you might ask “What’s in it for the rest of us? ” or “How much is this going to cost me?”. Good questions. In addition to expanding broadband access in general, one of the goals of the Broadband Plan is to provide average download speeds of AT LEAST 100 megabits per second (Mbps) and upload speeds of AT LEAST 50 Mbps. That sounds like a great deal to me. I’m “only” getting about 9 Mbps down with 1 Mbps up speeds right now.

So far I have seen very little about how this whole thing is going to be funded. If there is information about the cost for this system and how much it will cost users/tax payers it is very well hidden on the FCC web site. I did find an article that claims that this national broadband will cost “$12-16 billion over a ten year period”. But if you think about a network that will have an estimated 200 million users, at a rate of approximately $1.6 billion/year, that is only $8/month… not bad at all. Especially when compared to the $40-$60/month that most people currently pay for much slower broadband access.

The biggest complaint that I have heard so far is from the National Association of Broadcasters (NAB). Since the FCC wants to provide wireless broadband access to rural areas, they are going to require about 500 MHz of spectrum to do so. The broadband plan proposes that 120 MHz of that come from the digital over-the-air TV spectrum. Television broadcasters just spent tens of millions of dollars transitioning to all digital television last year and the NAB claims that if they lose some of their digital spectrum that it will simply cost them too much money. The FCC’s counter to that argument is that only one to two digital carriers in rural areas will really be effected by this bandwidth reallocation and if the broadcasters are innovative, there could be even fewer broadcast losses than that. One possible option is to reduce the size of the “deadband” between over-the-air television stations. Since broadcast is all digital now, it requires much less of a buffer zone between stations than old analog television did.

How all of this plays out will be very interesting to see. I have only briefly touched on the very long, dense list of things that the FCC would like to do with this plan. If this plan goes through, it is much, much more than just a broadband for everyone plan. If you would like to find out more you should check out the links in this post. You could easily spend days reading about all of the details of this potentially major change in communication standards in the United States.

2010
04/22
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iPhone Folly or Typical Apple?

I’m a little late getting to this topic since the news was released a week ago, but the latest developments in iPhone control have been very interesting to me. What’s that you say? It’s old news that you haven’t heard yet? Excellent.

On last Thursday, Steve Jobs announced that Apple would be making software for the iPhone more “secure” by no longer allowing any programs that are compiled using anything other than a C, C#, or objective-C compiler. What does that mean? It means that development for the iPhone will only become more difficult and some existing applications will disappear from the app store. As if Apple’s exclusive control of the app store was not enough. Any programs developed in Java or that use Javascript will no longer run after the next iPhone firmware update.

The biggest implication of this change that I have noticed  is that the application developed by Adobe to compile Flash files into an iPhone supported format will be blocked since it is based on a Java compiler. Not surprising, but a real bummer. Especially since the lack of Flash support is one of the biggest downfalls of the iPhone already.

On the other hand, there are always two sides to any story. A large part of Apple’s success is due to the fact that every product they have ever made has been mostly locked down. Up until just a few years ago, a Hackintosh was pretty much unheard of. But now that Apple has made the swap to Intel, homebrew Macs are popping up all over the place. But, the quality simply is not the same. Apple designs products from the ground up to work and to work well. I love my Macbook… and I like my iPhone. They both work very well all the time. However, I have never had a cell phone that did not work all the time. Granted, this is my first smart phone… but think about it.

In the personal computer market, Apple has never had a large portion of the market share. They have stayed alive and have a faithful following, but they have never been a real threat to their competition (at least since the first battles with Microsoft, Xerox, etc). In the smart phone market, Apple is certainly a leader. Sure there are RIM, Windows Mobile, and Android. For now, that does not appear to matter very much to Apple because the iPhone has dominated the market.

So basically, Apple has made it a little more difficult to develop applications for the iPhone. But it does not appear that it will be a major threat to their future sales. Ultimately, no one other than developers will even care. I have heard several times that technology follows the developers. We will have to see how the market changes over the next few years.

Stay tuned for my next post on my opinion of the future of the Android OS.

2010
04/16
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What exactly is 3G?

How many cell phone commercials have you seen that advertise how fast and wonderful their 3G network is? I know I have seen dozens, at least.  But very few people actually know what 3G means. For starters, 3G means third generation. Third generation implies that there was a first and second generation. However, the first and second-generation networks were not widely known as 1G and 2G. In this post we will take a brief look at the history of cell phone networks and try to discover what the mysterious 3G actually represents.

Motorola started the first generation of cell phone networks way back in the 1970s.  At this point, transmission was based on radio waves and all data was transmitted and received through frequency modulated (FM) analog signals. There was no encryption, so interception and interpretation could be accomplished with minimal equipment requirements. It was not until the 1980s that this technology became publicly available. Even then, the network was very unreliable and cell phones were mostly a novelty. However, technology quickly progressed to the second generation.

Second generation mobile networks offered some impressive upgrades. GSM and EDGE systems were introduced and have been in use since cell phones came into heavy commercial use. Also, text messaging and the ability to access media (ringtones, etc.) was introduced on the 2G network. The data rate went from a measly 10 kbps to an effective 64 kbps (using GSM technology). This fact, combined with the second generation using digital transmission schemes allowed many more users to send data through the network. Finally, encryption and error checking were introduced in 2G networks, which boosted network performance, reliability, and consumer confidence. Neither 1G networks nor 2G networks had official standards to comply to worldwide.

Now that we have the basics of earlier networks, let’s talk a little bit about 3G. Between 2G and 3G there was another speed bump. According to International Telecommunication Union’s (ITU’s) International Mobile Telecommunications for the year 2000 (IMT-2000), a standard 144 kbps data rate should be provided to users moving at a high rate of speed and 384 kbps should be delivered to anyone who is standing or moving slowly. One of the biggest technological advances for the 3G networks was the ability to reliably connect to the internet. The connection to the internet and significantly higher data rates allow 3G networks to provide consumers with a very effective, reliable connection to not only cellular service, but any information or web service that one could desire.

In summary, cellular networks have come a very long way since the 1970’s. Cell phones started out as bulky, unreliable devices and have evolved to be pocket computers with high-speed internet access thanks to 3G. If a 3G connection were available everywhere in the world, modern cellular networks may be as reliable as landline telephones. The truth is, if you actually have access to a 3G network it is almost as fast and wonderful as advertised.

2010
04/06
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First Post

This blog is dedicated to posts about wireless communications per a class assignment in EE418 at the University of Alabama at Birmingham. I have not yet decided on my first topic, but you can expect a post within the next week.

2010
01/23
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