M6L3: Common wireless technologies

[1] Bluetooth

Range = 10 meters

Speed = 1 Mbps

Frequency = 2.4 GHz  

Application: Computers & home appliances, laptops, mobile phones & Internet

Advantages: less power consumption & low cost

Working: It works with a microchip embedded in digital devices to transmit & receive signals.

Bluetooth device

(1) Hosted: the host must have necessary drivers/software installed to accept signals while the guest contains an embedded software. For e.g. connecting Bluetooth mouse with personal computer.

(2) Non hosted: Here there is no need for external software to be installed in the host device. Meaning all the required drivers are already embedded inside the system E.g. Bluetooth headset that is controlled by a cell phone.

Classification of Bluetooth

Baby Bluetooth

Very short range 5 meters to max 10 meters

Blue jacking

Send text message using Bluetooth connection

[2] Wi-Fi = Wireless fidelity

Frequency = 2.4 GHz (USA/India ) or 5 GHz (USA)

Range = 100 meters

Speed = 11-50 Mbps

Networking standard = IEEE 802.11

Working: Transmits signal via hotspot & receives signals by WiFi enabled device

Concerns:

Higher energy consumption

Battery drains down very fast

Less secured unless WPA protected.

Advantages

Moving P.C. can remain active on network

Can be enabled on LAN => can be expanded by adding more adaptor & access points.

Wi-Fi direct = Xender or Mi drop = peer to peer connectivity

Difference between Bluetooth & Wi-Fi

Bluetooth	Wi-Fi
Creates personal area network	Deployed on local area network
You create it personally	Given by network provider (e.g. GTPL or Spidigo)
Peer to peer connectivity	Follows networking protocol, thus registers IP address than starts its service.
Less bandwidth	More bandwidth (allows more users)

Blu-Fi Bangalore based company TELIBRAHMA has invented BluFi. It sends signal using Bluetooth to the router while the router returns signal through Wi-Fi using higher bandwidth. For a person who wants to save his battery from draining very fast, this technique offers a good solution. Recall the fact that Bluetooth consumes less power whereas WiFi needs more

[3] Wi-Max (Worldwide Interoperability for Microwave Access)

This technology can transport Wireless data along long distances (~50 kilometers). Thus, serves an alternate option to connect remote areas without using broadband cable or satellite.

It can offer enough speeds for using services like Internet protocol television, Voice over Internet protocol, Internet etc. It uses P2P (Point to point) or point to mobile/cellular access.

Difference between Wi-Max & Wi-Fi

Analogy = Mobile to mobile connection	Cordless phone (modem = fixed) & receiver = moving
Wide range	Short range
More costly	Low cost
70 Mbps	54 Mbps
2.4-11 GHz	2.4-5 GHz
IEEE 802.16 Standard protocol	IEEE 802.11 Standard protocol

Police/army use Wi-Vi during counterterrorism operations. This technology uses two transmit antennas and one receiver. Both antennas transmit the same signals, except one is the inverse of the other. This means that they cancel each other out when they hit static objects, because they create identical reflections. However, when a person is moving on the other side of the wall, the reflections change according to the movement. This new tech can be used in anti-theft alarms, to find people trapped in a disaster area; for finding criminals; video game gestures, and even the general public for when they're walking in dangerous areas or at night

[4] RFID

Like barcode that has a tag & a reader, Radio frequency identification device contains a

(1) Reader = interrogator with an antenna => sends E.M. waves

(2) Tag types = microchip with an antenna => receives waves

(a) Active = battery powered

(b) Passive = derives power from received signals or field created by the reader to power itself. Then modulates the waves & sends it back to the reader.

(c) Semi passive = battery powered only to run chips circuit => sends waves using passive method only.

Frequency types (1) HF (2) UHF (3) VHF

UHF & VHF = higher energy waves compared to HF.

Range = 300 feet or more.

Uses: active tags to find books in libraries, real time tracking of wildlife, locating lost assets, enhancing security, traffic/parking, Inventory management, consumer packaged goods, manufacturer, warehouse, retailer etc.

An EMV chip card is single card that allows payment through gateways like RuPay, Master-card & Visa. It is embedded with a microchip that will contain all the balance details & account statement. It is safer than the swipe card, since the latter contains a magnetic stripe that can erased or copied easily.

[5] Near field communication (NFC)

NFC is a branch of High-Frequency (HF) RFID, and both operate at the 13.56 MHz frequency. It is designed to be a secure form of data exchange, and an NFC device is capable of being both an NFC reader and an NFC tag. This unique feature allows NFC devices to communicate peer-to-peer. With ISO standards, it will allow a secure gateway for payment by using encryption.

Comparison all wireless technologies

Communication type	NFC	RFID	IR	Bluetooth
Setup time	< 0.1 milli seconds	< 0.1 milli seconds	~ 0.5 milli seconds	~ 6 seconds
Range	10 meters	3 meters	5 meters	30 meters
Usability	Easy & fast	Depends upon the type of item	Depends upon the size of data	Depends upon the size of data
Selectivity	Highly secured	Partly secured	Depends upon the line of sight	Can be kept invisible
Experience	Touch, wave & connect	Get information	Easy	Configuration needed
Application	Payment, sharing & to get access to data	To track items	To control & exchange data	Network for data exchange & headsets

NFC shares many physical properties with RFID such as one-way communication and the ability to communicate without a direct line of sight. There are however three key differences. 1. NFC is capable of two-way communication and can therefore be used for more complex interactions such as card emulation and peer-to-peer (P2P) sharing. 2. NFC is limited to communication at proximity, typically 5cm or less. 3. Only a single NFC tag can be scanned at one time. These properties were developed primarily to enable secure mobile payments and it is for this reason NFC is limited to singular and proximity interactions. An important by-product is that NFC is now available in most mobile phones and this is perhaps the most important difference between NFC and RFID.