Why Wi-Fi Operates on an Unlicensed Spectrum?

Yesterday a friend of mine asked me this question: “Why does Wi-Fi use unlicensed spectrum whereas WiMax, GSM and other cellular networks use licensed?”. That was a good question which I haven’t thought of before. I thought briefly and realized that I couldn’t come up with one answer. Could it be because of:

• Wi-Fi operates on that specific frequency band that happens to be for free (2.4GHz)?
• To make Wi-Fi a more cost effecient network so that more users can benefit from it (since licensed networks costs more)?
• Since it operates in a small range, it doesn’t need to be licensed?
• To make it easy to deploy?
• High level security is unneeded, since unlicensed networks is unprotected by the government and do not have the authentication and security that licensed networks have?
• The technology itself won’t work on any licensed frequncies?
• The government?

After noticing I gave too many answers, I knew that there must be a better clearer answer to that, so I decided to look it up..

At wikipedia they say: “The regulations for unlicensed spread spectrum enabled the development of Wi-Fi, its onetime competitor HomeRF, Bluetooth, and many other products such as some types of cordless telephones.”  So I guess that means that if it were to operate on a licensed frequency it wouldn’t of have developed the way it currently has.

In the mid 80’s the FCC made the unlicensed spectrum available and many countries followed as well which now allows the technology to be used anywhere in the world regardless of service provider and manufacturer.

At WiMax.com an article called Licensed or Unlicensed Spectrum: What are the options? shows the differences between licensed and unlicensed frequencies, the different frequency bands and their usages and some of the technologies used to prevent interference in unlicensed networks.

After reading a couple of other articles I noticed that some of my answers are valid reasons to why Wi-Fi took advantage of the unlicensed spectrum and perhaps there is no one reason for it. Do you have anything else to add?

 

I am Still Here

Yes I am still here.. Didn’t forget about my blog…. I know I said in my last post to be on the look out for new things but unfortunatly it has been a very busy time since then and I couldn’t write.. And now I will be on vacation soon so I guess I’ll be back after that..

Happy One Year

Its been exactly one year since I started my blog.. Before I created it, I used to write about these topics and send them as emails to my friends and contacts who were interested in technology. Then the idea of putting it all in a blog and sharing it with everyone came out and I am so glad I did. I love wireless technology, I love telecommunications and being able to share and write about it is now something I love to do. 

I’d like to thank those who gave me this great idea of having my own blog and would like to thank all my readers.. Always stay in the look out for the next post

The Wireless Corner… Happy One Year!

                                                                                                                     Tara

 

Things You Can Do With a Touch of a Cellphone

Instead of waiting in line to buy a bus ticket, a movie ticket, pay for groceries.. ect,  just tap your cellphone on a smart tag and your payment is done. While wondering which movie to watch at the movies just tap your phone on the tag of the movie’s smart poster ad and you’ll recieve the information you need about the movie. Touch another NFC enabled cellphone and share music, business cards and photos. All that is going to be possible using a technology called Near Field Communication or simply, NFC. (I talked about it briefly in a previous post).

NFC – Near Field Communication is a wireless technology that operates in the range of 4 cm on an unlicensed frequency band with data rates around 300- 400 kbps (about half the speed of bluetooth). The cool thing is that it works by tapping the mobile device with another NFC enabled device or smart tag and a connection is established immediately (in about less than 0.1 sec) to share data, access information, make payments.. ect. Due to its small range its rather secure and for making large payments the user should enter a password for authentication before the transaction occurs. This video on YouTube demonstrates some examples on what this technology can do. NFC is still being tried in many countries and devices that are NFC- enabled are expected to increase in the next couple of years. (Nokia recently announced  the Nokia 6212 NFC cellphone).

So the next time you’re at a vending machine and don’t have coins in your pocket for that candy bar, just take out your cellphone..

Want to Save Power?

Here is one way you can do that. Some of you might already be aware of this, but a good way to save up power is through your cellphone charger. People usually charge their cellphones while sleeping and you might think that once the cellphone has been fully charged no power is consumed (your charger starts cooling off too). Well, you’re wrong.

Charlie at Nokia conversations wrote in his lastest article that

” normal Nokia chargers draw about 150mA power when just plugged in and not charging a device (when the charger is on standby). ”

Compared to having billions of cellphones and chargers out there, thats alot of wasted power. Therefore, its best to unplug your charger once your cellphone has been fully charged. According to the article, Nokia is working on new chargers that will produce zero waste..

GPS Tracking Device with GSM Radio

Keith Shaw from NetworkWorld demonstates the new portable GPS device called the GPS Snitch in this video. The device provides two-way communications between the GPS satellites and  also has a GSM radio that allows two-way communications with servers so you can follow around anyone with this device in their vehicle as long as there is GSM coverage. Interesting..

Mobile Operator Vs. Mobile Carrier

I once read an article that refered to both a mobile carrier and operator in the same paragraph. And since then I was unable to get an answer to whether there is a difference between the two. As I understand, a mobile carrier is a mobile operator. I don’t remember where I read it so I can’t reference it now however, if there is a differenece between the two could you please let me know what it is?  

Nokia 6212 Classic: NFC-Enabled Phone

Nokia announced in its recent press release the Nokia 6212 Classic which is an NFC-enabled cell phone. I haven’t heard much about NFC before so I looked it up on wikipedia.

Near Field Communication (NFC) is a wireless technology that allows communications between devices in the range of 10 centimeters. You might think of Bluetooth but with a shorter range and a faster set-up process. According to the press release NFC will simplify and speed up the way people interact and exchange information:

“With the Nokia 6212 classic, people can swap items like business cards or calendar notes by simply tapping their handsets together. With ever-increasing device functions and services available, ease-of-use is essential. One way to keep things simple is NFC.”

And according to wikipedia, NFC can be used in many applications such as mobile ticketing, mobile payment and blutooth pairing. I recommend reading both links for more information about NFC.

Bypassing 3G to 4G?

I have been wondering about something lately… With all the buzz about LTE and the fact that it might be deployed commercially by 2010, what about those countries that don’t have 3G deployed yet and some even don’t have the license to operate it either and its not because they are not developed countries, I am talking about major operators. I read recently that the migration to LTE could be done easily from any of the 3GPP technologies (GSM, UMTS, HSPA+) and that LTE would offer seamless handover to these technologies when user out of coverage. So maybe these operators are waiting to migrate directly to 4G. Although I haven’t heard of such a deal yet. I know there could be many reasons not to have 3G; price of services, price of license and installations, users’ requirements, ..etc. But my question is this: When operators did not invest in 3G then why would they want to invest in 4G? If they did decide to do that then it won’t be any time soon and until then the user can only buy the device that supports it but not operate it.

The all-IP Cellular Network - LTE

Reading the article entitled The Packet Call Becomes History with LTE by Martin Sauter made me think about the future of the all-IP cellular networks which will come in the form of LTE.  In the article Martin wrote:

In LTE networks, however, a device without an IP address is completely useless. Hence, the LTE network attach procedure already includes the assignment of an IP address. Consequently, an LTE device will always have an IP address. 

That makes me wonder more about the LTE network. If every cellphone did have an IP address assigned, will it work in the same way as PCs do a network such as which IP class it belongs to, masks or even creating a subnetwork out of a group cellphone devices? Will it be a static IP or dynamic? What about security? Will there be enough IP addresses to be assigned to cellphones or should they move to IPv6?

I need to look more into this as I am not sure how those questions can relate to a cellular network at the moment. Will let you know once I get a clearer view on this..