Sunday, November 29, 2015

Optisystem for Researcher/ Academician working in Optical Communication Systems


Optisystem is a very useful software tool for researcher and academician working in the field of optical communication systems.

You can drag, drop and connect various components available in optisystem and get your results instantly.


This software is available here to be used for one month without having any license. There are many examples available on the site to get a feeling of the working environment. New Optisystem Lab assignments are there which can accessed free of cost.



Above snapshots shows the layout of Optisystem. The hot topic optisystem examples are available on the following website.




Thursday, November 26, 2015

Funding Opportunities for Postdoctoral Scholars

After completing PhD, the scholars look for opportunities to continue their research and look for postdoctoral funding. On this page, I have tried to summarize some of the funding opportunities available to them throughout world.

It is recommended to all the prospective candidate of postdoc to make ready a research plan to be sent to the funding agencies.  Some of the fellowships even like to have some recommendation letter in hand before application for that particular fellowship.


1. Fulbright Fellowships

A program of the United States Department of State Bureau of Educational and Cultural Affairs


2. Fulbright Canada


Foundation for Educational Exchange between Canada and USA


3. Endeavour Scholarships and Fellowships


Merit-based scholarships provided by the Australian Government that supports overseas citizens to undertake study, research and professional development programmers in Australia and for Australians to undertake these programs overseas.

4. Max Weber Postdoctoral Fellowships

For junior post-docs 

5. Marie Curie Post-doctoral Research Fellowships


Post-doctoral Research Fellowships Programme  by the European Union (EU) 



In most of the cases, at the end of post-doc, the researcher is expected to submit a postdoctoral fellowship final report of 5-10 pages. 

Tuesday, November 24, 2015

The History of Mobile Communications in Pakistan


Instaphone - It was the first company which launched mobile services in Pakistan. It commercially launched its services on October 16, 1990; however, this company lost its license in January 2008 as Govt. of Pakistan cancelled its licences due to unpaid fees.


Mobilink: First GSM based mobile network in Pakistan was established by Mobilink and it was  started on June 11, 1994. It has extended its 3G services in around 200 major cities of Pakistan. It is the largest mobile operator in Pakistan.


Telenor: Thought present in many countries in Europe and Asia and founded in 1855, it entered in Pakistan only in April  2004  and started to offer GSM services in March 2005. Since than it has become the second largest cellular operator in Pakistan.


Zong: Zong is a subsidiary of China Mobile which is the largest mobile operator in the world. It started its services with brand name Zong on April 1, 2008. It now not only has 3G license but also has 4G license in hand.


Ufone: Its Pakistani cellular operator which started GSM services on January 29, 2001. Its the fourth largest mobile company in Pakistan in terms of subscribers. It also has 3G services offered in major cities of Pakistan.
Warid: Warid entered in Pakistani mobile market on May 23, 2005. It is the fifth largest mobile company in Pakistan. It has purchased both 3G and 4G spectrum from Govt. of Pakistan.

Wireless Ad hoc and Sensor Networks

Wireless Ad hoc and Sensor Networks
Wireless ad hoc networks differs from cellular/mobile network in the sense that ad hoc network does not have any infrastructure while cellular network has fixed infrastructure to support communication among them.
Example of an Ad hoc Network

Friday, November 20, 2015

Monday, November 16, 2015

Device to device communications (D2D)

Device to device communications (D2D)

The target data rate of 1Gbps for the next generation mobile communications called 5G can only be achieved by introducing many novel techniques into the existing wireless standards of cellular communications. 

These novelty may come in the form of massive MIMO, heterogeneous networks, cooperative relay, millimeter wave, cognitive radio, adaptive beam-forming, device to device communications etc.

Device to device communications (D2D) is a way of communications where the transmitting as well as receiving pair exchange their messages without getting assistance from any infrastructure as opposed to cellular communication where the transmitter has to get help from the infrastructure to send its information to final destination.  This infrastructure include base station tower, mobile switching centre and sometime the gateway.

D1-D2 are shown to be engaged in direct communications called D2D communications.
D2D communications offers many benefits like increased data rates, reliability, interference reduction, power saving, traffic  offloading and use of licensed spectrum.

However, there is no such thing as a free lunch, hence, this charming techniques also comes up with its own challenge. The challenge of authorization. In other words, the D2D communications has to take place somewhere in licensed spectrum and it may create interference for the primary users, therefore, it puts extra burden on the network to handle the issue of authorization and authentication.

The following are the resources to get in depth knowledge of the fascinating field of wireless communications.

D2D Communications – What Part Will It Play in 5G?


3GPP Tech. Report 22.803, “scenarios and requirements for general use cases and national security and public safety,” May 2015.

M. Tehrani, M. Uysal, and H. Yanikomeroglu, “Device-to-device communication in 5g cellular networks: challenges, solutions, and future directions,” Communications Magazine, IEEE, vol. 52, no. 5, pp. 86– 92, May 2014. 

A. Asadi, Q. Wang, and V. Mancuso, “A survey on device-to-device communication in cellular networks,” Communications Surveys Tutorials, IEEE, vol. 16, no. 4, pp. 1801–1819, Fourthquarter 2014. 

D. Feng, L. Lu, Y. Yuan-Wu, G. Li, G. Feng, and S. Li, “Deviceto-device communications underlaying cellular networks,” Communications, IEEE Transactions on, vol. 61, no. 8, pp. 3541–3551, August 2013.  

R. Ahlswede, C. Ning, S.-Y. R. Li, and R. W. Yeung, “Network information flow,” IEEE Transaction on Information Theory, vol. 46, no. 4, pp. 1204–1216, July 2000. 

M. K. Frank H.P. Fitzek1 and Q. Zhang, “Cellular controlled short-range communication for cooperative p2p networking, vol. wg,” in Wireless World Research Forum 17, Nov 2006. 

M. Rodziewicz, “Network coding aided device-to-device communication,” in European Wireless, 2012. EW. 18th European Wireless Conference, April 2012, pp. 1–5. 

S. Shalmashi and S. Ben Slimane, “Cooperative device-to-device communications in the downlink of cellular networks,” in Wireless Communications and Networking Conference (WCNC), 2014 IEEE, April 2014, pp. 2265–2270. 

J. G. Proakis, Digital communications, 4th ed. McGraw-Hill, New York :. 

J. N. Laneman, “Cooperative diversity in wireless networks: Algorithms and architectures,” Ph.D. dissertation, Massachusetts Institute of Technology, Cambridge, MA, Aug 2002. 

J. N. Laneman, D. N. C. Tse, and G. W. Wornell, “Cooperative diversity in wireless networks: efficient protocols and outage behavior,” IEEE Transaction on Information Theory, vol. 50, no. 12, pp. 3062–3080, Dec 2004. 

G. D. Menghwar and C. F. Mecklenbra¨uker, “Network coding for cooperative communications,” Proceedings of Junior Scientist Conference 2008, Vienna, Austria, pp. 105– 106, Nov 2008. 

G.D. Menghwar, “Outage performance of two users cooperative network coding,” Proc. IEEE International Symposium on Communications and Information Technologies (ISCIT-2009), Sep 2009.


Friday, November 6, 2015

Cooperative Communications


Cooperative communications is a method of communications in which users in a common vicinity help each other for reliable transmission of their messages to the destination.