Android has not seeing much love from Japan. To this date, Japan has only 3 Android (international) handsets offered by carriers. HTC Magic came out about a year ago from Docomo, and they also released Sony-Ericsson Xperia X10 in April this year. Softbank meanwhile released HTC Desire end of April this year. And then very recently, both Docomo and AU KDDI released an Android smartphone, which looks more like a PDA. Here is Docomo’s Lynx: And here’s AU’s IS01: They might look the same, that’s because they are. They are essentially the same device, made by Sharp, with some...

I usually plug my HTC Desire to the computer USB to charge during day time and plug it to the AC adapter in the night. And I also carry this Eneloop battery if I need to charge while I’m out. Found some free time on my hand wanted to see how these three perform. So I basically drained the battery completely until the phone shuts down itself and then plug it to the power source. I tried to keep the conditions same for 2 hours of charging, starting from 0% charge. Here are the results: Connected to computer USB: Eneloop battery: AC adapter: Using computer USB and the Eneloop battery both...

First of all, kudos to Amazon for making Kindle available on almost all platforms. There still is no version available for Linux. A little ironic considering the fact that Kindle is based on Linux. But importantly they have an Android version. Many developers embrace iOS but still tend to overlook Android, but Amazon has made a full fledged version for Android too. Now to the features. Sync across multiple platforms – I use Kindle on iPad while at home and use it on my Android when I’m outside. I read to a certain page on the iPad, close the app, then sometime later open Kindle on my...

The internet is overwhelmed with iPhone vs. Android articles. This is post too is an iPhone vs. Android, but I will list up some  other (possibly minor) features which I found out myself. I haven’t used an iPhone, but I have used an iPod Touch since its’ first generation and my two of my immediate family members use iPhones. So I believe that I qualify to pass a judgment on the iPhone compared to Android (HTC Desire in my case). So here goes why I. wont. use. an. iPhone. Freedom – People, mostly iPhone users, chuckle when mentioning about the freedom Android gives. It’s sort...

First things first. I am not a Apple fanboy. Far from it. I am not trying to promote any Apple products but as a student, in this little time I had the iPad with me, what I can say is, I wish I had this couple years earlier. People claim iPad is just a big iPhone. I have not used an iPhone but I have used a first generation iPod Touch since it first came out. Since iPad cannot make any calls, I think it’s fair to say iPad is a big iPod Touch. For me atleast, it isn’t. iPad is ‘magical’, but not for the reasons Steve Jobs is claiming, but for the productiveness it can provide....

This is an important functionality I use in my simulations but when I want it I always have to search for it because I forget the Matlab function name. There are lots of loopy ways using random numbers to get this done, but there is an in-built Matlab function you can use: randperm(n). I often need to choose a set of values from a vector. For example, randomly choosing a set of users. Random numbers cannot be used because they can give you identical numbers. Need a method that would generate different numbers. What randperm does is scrambling a sequence of numbers. For example; randperm(5) = 3 1 4 2...

For some reason I prefer Ubuntu on my iMac 27″ compared to my normal desktop. It just looks good in it. The installation is straight forward. Lucid is still alpha but it feels solid (only one more month to go anyway) and it looks good. The purple theme is gorgeous. I first installed 9.10 and then upgraded. Below I post some pics. For a detailed installation guide refer to my earlier post on the iMac here. But note that MacBook Pro installation is less troublesome, because you do NOT need to go to the safe graphics mode to install. Just hit install Ubuntu. There is a documentation you can...

This is a follow up to the Cyclic Prefix (CP) I did here. There I gave a graphical explanation and here I will discuss how it happens theoretically. I recently came across the derivation in a text [1]. So here goes. Considering an N-point FFT system, a block of data points , is to be transmitted during a symbol time. The data vector is sent to an IFFT module. The operation of the FFT, i.e. the discrete Fourier Transformation (DFT) is given by the following matrix: where denotes the -th entry in the DFT matrix . Then the transmitted data vector after the IFFT operation is. . The normalization factor ...

Just yesterday got Ubuntu 9.10 installed on a iMac 27 incher. Here is small guide to the installation. Step 1: You need to partition your hard drive. Use the pre-installed Boot Camp Assistant program (Applications->Utilities->Boot Camp Assistant) for this. You probably will need to divide the drive in half because the other option of 32GB (I think) will not be enough. Step 2: Install rEFIT. This will give you a boot menu at startup where you can choose between Ubuntu and Mac OS X. Below is a screen shot of what you will see at start up (note: This is after Ubuntu installation). Step 3:...

This column will briefly explain how cyclic prefix (CP) in OFDM works by illustration. I decided to add this topic because the I seldom found a text that simply discussed the operation of CP and its usage. First, lets define a property of Discrete Fourier Transform (DFT) : If x(n) and h(n) time-domain signals, circular convolution between them x(n) © h(n) is equivalent to multiplication in the frequency-domain, X(k).H(k). That is, if we circularly convolve two time-domain signals, it is equivalent to multiplying the respective DFT’s of the time-domain signals in the frequency-domain. Now lets...