One invention that has changed the field of communication and put forward revolutionary developments in human life style is the invention of RADIO. With that invention unreachable has changed to reachable and untouchable has changed to touchable. Till the invention of radio long distance communication which made used of wire for transmission has changed to wireless and this paved the breakout of wireless technologies which lead to the invention of mobiles.
I am not going to tell about the invention of radio. I will like to share details about the new era communication technologies like Bluetooth and Wi-Fi. These technologies are not from a different family. It is included in the same family of radio. That is why I have mentioned about radio and its invention. We all know that Wi-Fi is faster than Bluetooth. What is the reason for this? After you have completed reading this article you will be able to answer this question.
BLUETOOTH
We are using it in our mobiles without knowing that what is the technology adopted behind it. The basic thing making use in Bluetooth is that the conversion of digital data into radio signals and vice versa. Two way communication is possible through Bluetooth. This is the basic fact. Now let’s see it in detail and its characteristics and factors which is to be kept in mind while using it.
The circuits or devices which make use of Bluetooth are cell phones, PDA and laptops. Also medical instruments are making use in medical sector. As we know that the above said devices were battery operated, Bluetooth technology operates in small power ratings. With small power ratings a range of about 10 feet is possible with Bluetooth. Also Bluetooth is capable of travelling through walls and other obstructions.
Radio signal of 2.45 GHz is used in Bluetooth Technology. This frequency is laid by the international standards so that other devices can be synchronized by constructing it to operate in this frequency range. The chance for interference of different frequency is minimized by making use of frequency hopping. Also large number of devices can operate at a time. Bluetooth uses spread spectrum frequency hopping. In this method a device uses 79 individual frequencies that are pre chosen. These frequencies will change rapidly and remain in the device for a fraction of second. Also more than one device which makes use of Bluetooth may be operating at different frequencies at a time. Also this method reduces the interference from electrical and signals from the surroundings.
While discussing about the security of Bluetooth, a device cannot access a provider without getting authorization access from the service provider. Device level security and service level security is made use in Bluetooth. This enables to provide security for private data. But this security doesn’t work on encryption basis and chances for hacking is more. So while playing with Bluetooth devices makes sure that you are secure by turning of Bluetooth when not needed or by turning it undetectable.
Wi-Fi
The advanced version of Bluetooth can be called as Wi-Fi. It uses the same radio technology for communication between devices. But the frequency and bandwidth of radio wave is different from that of Bluetooth. Wi-Fi provides two way communications with more speed than Bluetooth.
Now let us see how Wi-Fi works. The basic things required in Wi-Fi are a router, an Ethernet hub, a firewall and wireless access point. The basic working of Wi-Fi is such that the router is connected to the internet. It converts the digital data and transmits as radio signals. Devices which have Wi-Fi can access this internet and thus wireless access become possible.
The frequency spectrum of Wi-Fi signals lies between 2.5 GHz to 5 GHz. This frequency is higher than that used in cell phones, television and radios. Wi-Fi is also called 802.11. It got this name from IEEE. IEEE uses this type of codes for naming different technological protocols.
We can classify the Wi-Fi signals into different categories based on the frequency and speed of transmission of signals. They are
802.11a-This works at 5 GHz frequency and is capable of transmitting at a speed of 54 MB/s. This method uses orthogonal frequency division multiplexing. This is an efficient method for splitting of signals before they reach receiver.
802.11b-This is the slowest but cheapest way of using Wi-Fi. It uses 2.4 GHz for transmission and can achieve a speed of 11 MB/s. This method uses complementary code keying modulation technique.
802.11g-This also uses 2.4 GHz for transmission. But it can achieve greater speed because of the use of orthogonal frequency division multiplexing.
802.11n-The new method of Wi-Fi which uses orthogonal frequency division multiplexing which can achieve a speed up to 140 MB/s.
With Wi-Fi we can get a range of about 30 feet which is sufficient to make a small building wireless.
But Wi-Fi faces some security problems while comparing with that of Bluetooth. Bluetooth is closed transmission methods and one cannot access it without the permission of service provider. But Wi-Fi is open. Anyone in the Wi-Fi hot spot can access it. This will create problem while the transmission of sensitive data. Although security can be introduced in Wi-Fi there are more holes in Wi-Fi rather than in Bluetooth. So be aware while dealing with Wi-Fi.