Category Archives: MOBILE COMMUNICATION

Difference between Conventional and Wireless Communication Systems

Published by:

Wired / Wireless

Conventional and wireless are the two different systems used for communication. A very notable difference is the presence of wire in the conventional communication system. The techniques used in both systems infra structure are same such as core elements of the network services. A wired network communicates through wires while wireless communication systems utilize radio waves.

 Complicated / Non-complicated

Conventional wired communication system is uncomplicated to install and fix but wireless communication system is complicated to establish. Its maintenance and troubleshooting are not possible without expert.

Mobility / immobility

Immobility is the bigger flaw of wired communication system as it makes you reluctant to not to leave your place in any condition. Wireless communication system gives you the ease of mobility and u can sit wherever you want while doing your work.

Costly / Cheap

An additional cost in the form of wires and cables is attached with the wired system and makes the budget heavy while wireless communication has no issue of cabling and the price is very affordable.

Speed:                  The transmission speed of the wired network has given it an edge over wireless system. In wired system, there is no need of sharing space and therefore no user interface. Wireless communication system has to share it band with sometimes multiple users that may reduce the transmission speed.

Seen / Unseen

Wireless system makes you excite to do uncertain thing like it transmit data (command to play n share music, print the document, and sharing of files) unseeingly with the help of radio waves. Other examples of the wireless communication system are Bluetooth and cordless phones, etc.

Reliability

Conventional communication systems as wired or Ethernet are coming in most powerful form as they promise to give you good speed nearly 1000 Mb/s that is faster than previous and all other Types of connections plus enhanced security as well. Further it is not a big deal to get high speed and security at reasonable price. Hence a wired system is more reliable than wireless.

Home Users / Corporate Users

Wireless network could be a good choice for home users as it works better and speed is not a big issue. In an office environment, however, wired communication system is preferred as there is need of high speed data transmission and security. However, as the offices are becoming mobile so there is demand for wireless system to take portable data. There is no such fuss in case of wireless system as downtime that is an issue in wired system. Wireless system is easy to install as Wireless USB helps you to connect in few moments. To change the place of a system in office just takes the system to the desired place with the card.

 Hotspot

Hotspot is becoming a popular term associated with wireless system. Internet is provided to the user as a promotional package by the owner in public places, libraries, hotels, schools, airports, railway stations to facilitate the users with it and entice them as well. In case of wired network you have internet access only through wire, there is no concept of hotspot.

Quality of  Service (QoS)

A negative point of wireless communication is the quality of service (QoS). It has no surety to have constant receiving of powerful signals as environmental changes and other hindrances (walls, birds or planes) may interrupt the signals.

Virtual Network

A positive point of wireless communication is in the form of WLAN as it makes virtual network by the users in its vicinity like university or library. It provides them wireless internet access. There is no need of access point to be connected with the internet.

Disadvantages of WRAN

Published by:

Traditional media and technology blogs have fled with the reporting of the recent approval given to the IEEE for using the supposed “white spaces” present in the UHF and VHF TV channels for wireless standard recognized as 802.22 that claim to be able to cover area of 100 km around the transmitter point. The theory said to install a router that will enhance the coverage of personal broadband with extra 62 square miles however practically it doesn’t seem feasible.

In reality local home consumers do not have any advantage of this new technology. The intention of introducing this new standard is to fetch the far off consumer at global platform. In easy language, WRAN is for rural areas where cable, DSL, and broadband technologies are not able to reach. The local consumer has no benefit of this WRAN. After continuous pressure by the companies like Google, Motorola and many other, FCC has been approved its used since last year. The approval is for those unused low frequencies present in useless form. However the use of WRAN is not easy and without permission. It needs a provision certificate that will be located by GPS to record the exact location of each transmission site with a central coordinating body. It is compulsory for the providers to release the channels in case of interference found because of WRAN. There is an alternative approach to access the channel one after another yet significant limitations in the number of available white spaces in existing channels occupied by different television broadcasting companies.

Theories are showing bright future prospects for the WRAN implementation but practically its application seems very rare and in rural areas with signs of little or no local broadcaster to respond. Considering the FCC amendments for the unlicensed use of white spaces, many of these are already grasped by American mobile companies, leaving even fewer open channels for this type of wireless broadband. There are very few chances in large urban areas that many channels available for IEEE 802.22 standard. Currently, FCC determines these networks cannot operate in a broadcast channel or channels occupied adjacent to each side. A channel 31 occupied in a city cannot let 32, and 30 channels to be operated by WRAN.

Now if we see the bandwidth offered to WRAN for individual consumer. A channel with 6MHz bandwidth can offer a real 12 Mbps service to a user. The IEEE specifies a maximum speed of 22 Mbps, but it is only in theories and seems nearly impossible as the consumer is very far from the transmitter and the available bandwidth is not capable to access it. Suppliers are going to make packs of multiple users for every channel. A number of customers while using the service probably would be half to 1.5 Mbps that is not a saturated level at good high speed and become equal to DSL speed. Overvaluation subscription for the network and use of the available channel at the same time this will surely sacrifice the speed. The increase in the subscription over transmitter would decrease the speed comprehensively.

There is one solution provide to this speed problem by adding more transmitter to increase the speed but installation of so many transmitter is depended on the availability of white spaces. There number of transmitters are proportional to available white spaces the limit cannot be exceeded. It is therefore only limited to rural areas where users are few and TV channels are less and periodical. Local users are not supposed to access this service and have to wait for some new advancement in the utilization of white spaces.

Cognitive Radio

Published by:

Cognitive radio is a wireless communication tool. It is used to take maximum advantage of the available communication channels. It is radio equipment known as transceiver which helps to identify the maximum capacity to send and receive the signals. It is a sort of channel detection tool to make the communication efficient and effective. It is the efficient manager of communication channels as which is preoccupied and which is not. Furthermore, it helps to utilize the free channels and reduces the resistance and prevent any hindrance comes in the way of broadcasting.

In a concise way, Cognitive Radio is a technology which helps to improve the spectrum bandwidth. While deploying in a certain area it performs functions as;

  • Detect the area of communication
  • Tell about the user’s occupied channels and non-occupied channels
  • Transcript the signals
  • Identify any wireless device in the nearer locality
  • Provide information about the unused bandwidth

Cognitive Radio takes into account two different scenarios;

  • It acts like a full cognitive radio which is independent equipment for wireless communication to perform multiple tasks.

OR

  • It acts like an electric eye to monitor the available space in the radio spectrum.

However, to a certain extent it is used for optimizing the bandwidth for new users with positive results.

Techniques

Cognitive Radio uses various techniques to perform the function of channel detection.

Detect through Transmitter

It is capable of identifying the transmitter signals far or near. It performs this job vigilantly in multidimensional ways. These can be adjacent course recognition, capacity recognition, and recognizes the cyclostationary characteristics.

Cooperative Detection

This is the method used in spectrum sensing. It provides the information about the specific user out of many users. It minimizes the chances of interference among many users. This is known as interference based detection.

Spectrum Management

It manages the distribution of many channels in the available spectrum. It tries to accomplish the spectrum with number of users. This function is executed through range analysis or range decision to improve the service.

Spectrum Mobility

In this technique available spectrum is used in the best possible way to meet the frequency demand. For this spectrum can be exchanged between different users with the change in frequency. This is known as frequency mobility which eases the communication in very condition.

 Spectrum Sharing

Cognitive Radio harmonizes the spectrum shared among many users. It gives flexibility to the spectrum to allow many channels to reside. Open spectrum offers challenge to cognitive radio for spectrum sharing same is the case with media access control.

Mechanism

Broadcasting channels through radio requires specific frequency to proceed. Antenna is used to cover the range for receiving the channels. This antenna identifies the signals in range by sensing the frequency. Cognitive radio helps to identify the frequency spread in the surrounding. There are many different frequencies strike the transceiver. You set your on channel by switching on the receiver and match the frequency and the transmission completes. Different other radioactive devices can interrupt your channels frequently as it detects every incoming signal in the given spectrum. Diverting the call to another frequency will clear the channel.

Usage

It is used to maximize the bandwidth.

It is used to reside every nearby channel.

It establishes connection with the nearby available spectrum to connect.

It allows different networks to exchange and cooperate.

It improves the signals to make the transmission clearer.

Potential

Cognitive Radio has a potential future as it is helping in prospering wireless communication to large extent. It is crossing the boundaries to support any upcoming channels to survive. It supports the connectivity and accessibility in every condition.

Android Features

Published by:

Android is leading among all the latest and the most advanced operating systems. The reason is all those features offered by its update versions one after and other till launches the seventh edition in the market. Android is offering countless features after the first version Android 1.1 launched in 2009.

 The very first version was so welcomes in just 8 months there comes three more versions of Android with more advanced features. Among them are cupcake, Donut and Éclair are the tasty feat give entertainment on the same level.

In the upcoming year in 2010, Froyo and Gingerbird came and had sizzled the market with crispy appetizer for human mind. This appetizer increased the need for more which is fulfilled by the latest version Honeycomb.

As there are total of seven versions has been introduced since 2009 however there are uncountable features present in totality. That is the reason of Android popularity among its users.

  • Marquee Screen

The very first and the instant attention gathering feature of Android is its marquee appearance. You find a large playground to play freely. In simple words the screen is very large and you can go for your personal choice whatever you want on the home screen. Android is giving support to extra large layout and maximum resolution to enhance the visual experience.

  • Texting & Snapping

The way to send and receive SMS and MMS are modified in a way that one can do SMS in a chatting style and can take snap and send it through MMS. Push Messaging service is introduced with the concept of cloud known as C2DM (cloud to device messaging framework).

  • Mobile Cyberspace

Android has made the mobile a wandering cyberspace as different internet technologies among them are GSM that is known as EDGE, IDEN and CDMA are included. Furthermore internet is accessible through Bluetooth, LTE, Wi-Fi, WiMAX, EV-DO, etc. as well. This concept of mobile cyberspace has changed the way of living. Now office can be managed from a distant place quite easily and there remains no restriction for a physical office.

  • Browsing World

Google after making its rights reserved has made it open for the users to use it as per their choice. Google is supporting its web browsing capacity through Chrome V8 JavaScript and enhancing the web browsing experience.

  • Unique Multi-tasking Tool

Android phone is not just a phone, it is rather multi-in-one tool. You can use the Android phone as Global Positioning System (GPS), as a camera in which you can take pictures and also can make videos, It is a great gaming tool to work as a jockey. It works as an accelerometer, magnetometers and gyroscopes.

  • Media Support

Android is an amazing big pool to have millions different applications in it. A person can go for an unusual wish to come true with the help Android. Media and Streaming media support are the two more features you can enjoy while having Android. Among various supported media formats are MP3, MPEG-4, HTML progressive, Adobe Flash Streaming and HTTP Dynamic Streaming with the addition of Flash plugin.

  • Video Chat/ VoIP

Android enables the users to make video calls  and this becomes possible for it being an open source as this is not Android inbuilt feature still you can enjoy this in Android.

Another great advantage of Android is its inbuilt applications of gtalk and skype that enables the users to talk through internet with IP.

  • Personal Hotspot

Tethering is an awesome feature that allows Android to work as personal hotspot either wired or wireless after the launching of 2.2 version of Android.

 

Advantages of Cognitive Radio Networks

Published by:

Cognitive Radio is miraculously helping technology available to the current increasing numbers of users in this century. It allows constructing a network of radio stations with the combination of cognitive radio nodes hence gives significant boost to the speed and availability of channels for the new secondary wireless networks.

There are two possibilities to access vacant channel. One, CR contact to multiple non CRs transmissions where femtocells get cognitive inspection, erect and then communicate with non CR mobiles. Two, CR networks would like to contact to the network and operate through the cognitive radio network. This type of networking has many advantages and benefits and capable of employing many useful applications for improving the performance of the entire network as the individual parts.

Cognitive radio networks are more feasible as compared to the single cognitive radio.

It improves the capability of spectrum sensing while gaining this characteristics cognitive radio networks offer many more advantages of significant value. The purpose of using cognitive radio is to utilize the spectrum in efficient way. Spectrum sensing is the basic function of cognitive radio networks and gives security with surety that primary channels would not be disturbed.

Spectrum sensing is the worthy action of the cognitive radio network to improve the spectrum effectiveness. CR spectrum sensing methods should be able to get update information about current transmissions running by the primary users and sends information back to the CPU (Central Processing Unit). There in the main system plan of action would be suggested and immediate command is prompted to the Cognitive Radio Network for the next step.

Cognitive radio networks also improve the coverage by relaying technique from one point to the next node. It helps to reduces the power consumption and does not sacrifice performance of the network.

What is ZigBee Technology – ZigBee Features & Applications

Published by:

What is ZigBee Technology

ZigBee Technology is one of such progression in wireless technology. Wireless is not a new technology as wireless networking and wireless internet are already in use; yet ZigBee technology set a new aspect in wireless technology. That’s why it’s usually referred as ZigBee Wireless Technology. Day by day advancement in technology is introducing novel and supportive devices which are used to make life easier and ZigBee Technology is one of them.

To better understand the ZigBee technology it is necessary to know what is ZigBee Technology? It is based on “MICA2DOT433MHz” which is a low-power frequency, works like a Bluetooth and uses the features of wireless networking. Keep in mind the plus points of each three you can evaluate its worth.

Using the networking system ZigBee Technology can connect machines and control through one connection whiles consuming less power. So ZigBee is the cost-effective wireless technology for controlling and monitoring.

ZigBee Technology Features

ZigBee technology has many useful features and characteristics and these features of ZigBee technology are the reason of its increase demand in the commercial zone particularly in commercial and residential at time lesser but prospects are better.

ZigBee technology allows wireless networking to connect several units to control through one button like in business industry. This wireless networking avoids the threat of short circuiting. Centralization control system reduces the man power.

As a wireless communication system ZigBee technology helps to monitor the activities and manipulates in a better way.

ZigBee technology used in the remote control devices helps to control the function at a specific range. This feature of ZigBee Technology is very attractive and effortless as all the home appliances are mostly coming with remote control system which is the essence of this ZigBee wireless technology. In industry all the units are centralized in one place with the help of remote control or switch-based system.

As ZigBee technology based devices are designed on low-power frequency therefore are reliable. Low-power consumption feature of ZigBee technology helps to run a device for a long duration or sometimes this duration is of years.

Bluetooth application gives a unique feature of transferring information or data from one place to another in a far better way than Bluetooth itself.

Zigbee technology is used in three different types of devices which are used in networking according to its functionality. As prominently ZigBee is a wireless technology for making a network system, coordinators are the primary devices to help in activation of the system by collecting the data in form of memory. Then router comes as a secondary device to perform the function by sending information to the destination. Third types of ZigBee based devices are the end-user devices. These are basically receiver so are not able to send information itself. It remains in sleep mode while not in use so less amount of battery uses and resultantly longer life.

Applications of ZigBee Technology

Applications of ZigBee Technology is not limited to a certain level but because of being cost-effective, low-power battery and wireless connectivity, this ZigBee technology is used in almost every appliance if not in all.

ZigBee technology is programmed in a chip form and is used in many devices to function automatically. For controlling and monitoring a whole factory unit while sitting in one cabin is possible by using ZigBee technology. It centralizes all the units in one place and enables the remote monitoring.

In a similar way, a home can be centralized by increasing the security aspect. Many small equipment’s are coming with embedded ZigBee technology chips and really works like a miracle.

ZigBee technology is swiftly prevail the market by introducing devices like smoke and heat sensor, medical and scientific equipment’s, control units of home and industry and wireless communication devices.

The revolutionize turn in the field of technology with the introduction of ZigBee technology; the near future of ZigBee technology will prevail in almost every walk of life.

Zigbee Networks

Published by:

ZigBee networks provide the most modern technology infrastructure for wireless devices and other electronic instruments with extra benefits of cost-effectiveness and low-power usage. ZigBee networks are widely used in huge industrial plants to formulate one monitoring and controlling unit. ZigBee networks are spreading rapidly in home environment by replacing the manual controlling of a device with one remote control.

How ZigBee Network works

ZigBee networks uses Coordinator, router (optional) and End Devices to communicate. ZigBee technology based network devices like coordinators, routers and end devices are used to form a ZigBee wireless network. In a ZigBee networking coordinators work as a primary device. It is a source to commence a networking process. Coordinator sends information to the router. These routers are secondary medium which acts as a bridge between coordinator and end device. An important point to remember is end device only works as a receiver within crucial time span less than 15msec.

ZigBee Network Topologies

ZigBee networks also follow different topologies like peer-to-peer and star topologies. First topology known as peer-to-peer topology is networked directly to each other through ZigBee network nodes. One node of ZigBee network device has the option of connecting multiple items hence the ability to form a network.
In peer-to-peer networking topology one node of ZigBee network device is connected with the other node for network formation and form a grid like structure. ZigBee networks offer short range wireless networking with a remote. For further clarification we can say that ZigBee networks relatively form a simpler network without any complexity.

In star topology of ZigBee network, all the devices have one central control unit and devices are attached through coordination with the help of multiple routers to increase ZigBee network range. It is a complex module and is difficult to tell which node is connection to which node but still in case of any breakdown the ZigBee network itself does not get affected and find an alternate route to perform the command sending through coordinator.

Cluster tree topology in ZigBee network is like mesh topology in essence. These clusters are like fruits attached to a central trunk and are ready to be eaten. These clusters are many stars with routers ultimately connect with the coordinator to form a ZigBee network. As per its structure this is the most used ZigBee networking plan in industrial units. ZigBee network never stops its function even if one device or even a one star is not in working condition. By using ZigBee network features of instant connectivity with the immediate available node it continues its function.

A wireless device with low-power deployment has a less danger and easy maintenance. It is like an automatic network to work through a single control system. While not in use the device instantly goes to sleep mode and this feature helps to increase the lifespan of battery. As compared to Bluetooth device it does not need recharge after every use. That’s why ZigBee technology is the most compatible technology presently restricted to industrial zone by using ZigBee networking but near future is of home centralization for security purposes based on ZigBee networking.

ZigBee Network Features

ZigBee Network speed

ZigBee technology presence in any device has a very exclusive feature of enabling the instant networking.

ZigBee Network Capacity

Zigbee network has a capacity of connecting more than 65,000 devices through different networking topologies. The data travel through this range from 20Kbps up to 250 Kbps.

ZigBee network Standards

The standard use in Zigbee networks is IEEE 802.15.4 and is effective in low-power signals. As compared to Bluetooth, Zigbee network covers a wide range from 10-40m.

ZigBee Architecture

Published by:

Before discussing the ZigBee Architecture let’s begin with understanding of ZigBee Standard (802.15.4). ZigBee architecture characteristics are parallel with Bluetooth; I said parallel not replacing it.

Considering the ZigBee standard this will show you the basic features of ZigBee technology.

IEEE 802.15.4 specification;
802 = networking group
15 = wireless network
4 = low data rate consuming less power

Comprehensions of ZigBee architecture help you better understand the function of remote controlling and monitoring. ZigBee architecture is based on the following blocks. The upper layer is application layer with nodes to attach the end device and lower is the data / link layer make bridge in between both upper and lower layers there is network layer to carry out the function. This whole model is known as stack as all the layers form a stack.

The ZigBee stack architecture is based on three major components; ZigBee Physical data/link level, ZigBee network layers and ZigBee Application support layer.

ZigBee data / link level is comprises of two layers. One is physical layer (PHY) and the other is Media Access Control (MAC) sub layer. Physical layer is responsible for sending and receiving the data from resource. Media Access is responsible for networking and acts as a sensor try not to collide hence initiate the command.

ZigBee network layers adhere to function by enabling the correct use of MAC and act like a bridge by making networks based on topology by using between application layer and ZigBee data / link level. These ZigBee network layers are responsible for networking and security matters. It enables a network and manage end joining or leaving. It is able to find another route in case of not availability of the immediate route and switch to the nearby route.

Application support sub-layer is responsible for input and output though from end device. It fulfills the data and management services. As the name implies that it supports applications and performs services for endpoints and ZigBee device objects.

Application Objects are the devices for which the whole ZigBee architecture is designed. These application objects are called endpoints. These application objects are placed at the top position in ZigBee stack architecture.

Application objects are managed and monitored by Zigbee device object (ZDO). Zigbee device object initiates the process of Data / Link layer by adopting the specific network topology and decides its function like coordinator, router or end device.

The Zigbee stack architecture supplies security measurements. It distributes its services into different layers MAC, APS and NWK securing the data loss hence provides multi level security.

Mobile Phone Security

Published by:

Advancement in technology where make you mobile there rises some serious mobile phone security issues as well. While you are mobile phone with some positive purpose like on a business trip there might be someone else mobile phone with negative intention to harm you. You don’t know where and how you get loss to your data within your mobile phone, but you can take precautionary measurements to secure your mobile phone important data or personal possessions.

When you are away from your home with mobile device like mobile, laptop or iPod you are exposed to the danger. It is your duty to take some precautionary measurements for securing mobile phone data if you are mobile. There are some different aspects you have to consider as to what and how should be secure.

It is your first and foremost duty to think what are the important information and data you don’t want to leak out. This information could be;

  • Customer’s contact information.
  • Client detail.
  • Personal data like personal number, birth date, CNIC No., and home address etc. It is advised that delete personal data while you are mobile or write partial information.

You must be aware of your need as which information you need while you are mobile.
While mobile, taking your all data with you could be harmful as you could lose your mobile phone device. Therefore it is necessary to place important data on a server machine instead of saving the information in laptop or mobile phone. In case of keeping data locally it is necessary to install software for the mobile phone security.

It is better to copy all the important information on CD and write short description about the data and arrange them date wise. This will help you to organize the data and also secure it in case of device failure.
Anti-Virus software or security updates are recommended to upgrade so that it regularly checks the files to avoid the data loss threat to mobile phone.

Hackers are clever enough to hack your passwords and logins information. Your password must be strong enough to be secure in any worst circumstance. For the strong password read the guide for strong passwords. Do not check the password remembrance prompt. Do not write password anywhere to be easily find out by someone. Do not allow cookies to save password on your mobile phone device.

Now-a-days wireless devices have in-built internet connection button. Switch-off this button not to establish connection automatically with an unsecured wireless internet. Do not remain on the sharing property of printer and file.

Always use secure wireless connection for the file and photo sharing and transferring.
While you are on move it is necessary to be very careful about your belonging. In public places you should be extra conscious about your surroundings. Keep an eye over your luggage and do not show off others that you have something precious something important. Do not let others to see your laptop or mobile, they can run away with it.

Do not let the Bluetooth on so that other can transfer important information without your permission. In case you forget to switch off the Bluetooth, you can be easily traced and trapped.

Let suppose you have lost your mobile or laptop. Do you have back up for the important information save in that particular mobile phone or laptop. It is better to secure information somewhere else away from your mobile device so that in case of robbery or loss you should not suffer the loss.

It is true that mobility helps you to be more productive and confident and surely has many advantages there is only need to be more aware to the threats and danger offers by outer environment away from your access.

Mobile Communication Technologies – Mobile Communication

Published by:

Mobile communication allows transmission of voice and multimedia data via a computer or a mobile device without having connected to any physical or fixed link. Mobile communication is evolving day by day and has become a must have for everyone. Mobile communication is the exchange of voice and data using a communication infrastructure at the same time regardless of any physical link.

Mobile communication technologies not only benefiting businesses to perform their operation faster and efficiently but also raising the standard of human lives. Mobile communication or mobile computing is just the two different names for the ability to use the mobile technology while on the move, most of the portable computers and computing equipment which are particular for the use in stationary place or configuration.

Ever since the population has been increasing, it urges the need for communication. Human beings are constantly busy to build up the easiest and the quickest way to communicate. Advancement in technology as the invention of telephone is one of such examples. Every coming generation is marked with one step ahead. Bigger telephones continuously passes through the modification process till the first mobile phone introduced. This journey of mobile communication technology started from late nineties with the 1st generation mobile technology has now reached till 3rd generation totally changes the canvas of communication mode. Third generation of the mobile phones virtually shrink distant places of the earth into a global village.

There are so many types of mobile computers, such as laptops, PDAs, PDA phones and other mobility devices were introduced in the mid of 1990s including wearable technology as well. And to use these types of mobility equipments we need to use right technology to make it more secure and reliable infrastructure. If we talk about the mobile communication technologies we can count on many mobile technologies available today such as 2G, 3G, 4G, WiMAX, Wibro, EDGE, GPRS and many others.

Mobile computing or mobile communication technologies based on different security standards and as well as the transmission protocol behind it. In this section we have discussed in detail about different mobile computing technologies and mobile communication systems. What makes mobile communication or mobile computing different from other wired and wireless technologies.