Analysis of GFDM as a robust 5G communication technique in noisy environment

One of the challenges of modulation techniques used in Fifth-Generation (5G) is their robustness in noisy environment. Conventional Orthogonal Frequency Division Multiplexing (OFDM) cannot be considered as a 5G waveform in its original form because of its certain limitations, such as performance degradation by impulsive noise (IN) and high peak to average power ratio (PAPR). Numerous modulation schemes proposed for 5G communications are able to overcome these drawbacks. Generalised Frequency Division Multiplexing (GFDM) is one of them. This paper analyses the performance of GFDM in presence of Additive White Gaussian Noise (AWGN), IN and Narrow Band Interference (NBI). It is found that GFDM is able to perform better than OFDM and Vector Orthogonal Frequency Division Multiplexing (VOFDM) in presence of noises, which can potentially be present in 5G applications. Simulation results show that GFDM achieve lower PAPR and Symbol Error Rate (SER) and an average of 10.73 dB and 4.73 dB gain in Signal to Noise Ratio (SNR) in presence of IN and combined IN and NBI respectively, as compared to OFDM and VOFDM

Nonuniform Sparse Recovery with Subgaussian Matrices

Compressive sensing predicts that sufficiently sparse vectors can be recovered from highly incomplete information. Efficient recovery methods such as $\ell_1$-minimization find the sparsest solution to certain systems of equations. Random matrices have become a popular choice for the measurement matrix. Indeed, near-optimal uniform recovery results have been shown for such matrices. In this note we focus on nonuniform recovery using Gaussian random matrices and $\ell_1$-minimization. We provide a condition on the number of samples in terms of the sparsity and the signal length which guarantees that a fixed sparse signal can be recovered with a random draw of the matrix using $\ell_1$-minimization. The constant 2 in the condition is optimal, and the proof is rather short compared to a similar result due to Donoho and Tanner

Contribution of Services Sector in the Economy of Pakistan

The services sector has provided steady support to Pakistan’s economic growth. It share in GDP now stands a more than 50 percent. The paper analyses its continuation in the growth of the economy in general and the development of trade and genera tion of employment in particular. The study identifies the bottlenecks in its growth and suggest measures to remove them. A set of policy reforms has been suggested to make the sector more effective in the growth of the national economy.Services Sector, Industry, Employment, Financial Institutions and Pakistan’s Economy

A Simulation Analysis of the Debt Problem in Pakistan

The current debt situation in Pakistan and the resulting financial crisis require serious attempts to find a sustainable indigenous solution. As such it is essential to search ways and means to reduce dependence on external borrowing over medium to long run.1 External debt is usually created to sustain a growth rate of the economy, which is otherwise not feasible with the given state of domestic resources, technology, consumption propensity and economic management practices. However, the success of economic growth financed by external borrowing depends on two factors, namely the domestic saving rate and productivity. A country with lower saving rate needs to borrow more to finance a given rate of economic growth. In Pakistan the flow of external loans is likely to have adversely affected the compulsion for savings. For example, no serious attempts have been made to improve tax collection or to control non-development government expenditure unless forced by the donor agencies.

The Response of Karachi Stock Exchange to Nuclear Detonation

Stock markets are highly reactive to internal and external developments. News of major events take no time to impact, the Stock Exchange that quite often serves as a barometer of the good and bad for the market. The importance of particular events and their effect on the stock market has been a subject of study in financial literature. Such studies attempt to assess the extent to which stock markets’ performance stray’s from the normal around the time of the occurrence of subject events. The stock market crash in the USA of October 1987 and related crash in the Far East later in January 1998 led to several studies of the event. On October 14, 1987, the US stock market began the steepest decline of its history, culminating in the crash of October 19, when the Dow Jones Industrial Average fell 508 points (22.6 percent). Certain aspects of the event of Black Monday as it is called emphasised the need for research to explore what fundamental economic factors triggered the large decline and the institutional and structural factors that were inherent in the trading strategies of investors. Michell and Netter (1989) have presented evidence that a tax bill containing anti takeover provision proposed by the U.S. House Ways and Means Committee of Oct. 13, 1987 was the economic event that triggered the October 19 crash. Other events and economic conditions during October 14–16 have been cited in the literature including higher than expected trade deficits, rising interest rate and increased worries about the government deficit and fear of inflation by many studies. Certain trading strategies such as index arbitrage and portfolio insurance has been cited by the Report of Presidential Task Force (1988). Roll (1988) has argued the crash did not begin in US since many other world markets experienced a severe decline on October 19 before US markets opened.

In vitro Evolution and Engineering for Improved Ribozyme Polymerase Production

According to the "RNA World Hypothesis" the first self replicating molecule formed from the prebiotic chemicals is the ribozyme. A model compartmentalized self replicating system for ribozyme polymerases is designed and used to improve activity, fidelity and generality of the enzyme