Wideband P-Shaped Dielectric Resonator Antenna

A novel P-shaped dielectric resonator antenna (DRA) is presented and investigated for wideband wireless application. By using P-shaped resonator, a wideband impedance bandwidth of 80% from 3.5 to 8.2 GHz is achieved. The antenna covers all of wireless systems like C-band, 5.2, 5.5 & 5.8 GHz-WLAN & WiMax. The proposed antenna has a low profile and the thickness of the resonator is only 5.12 mm, which is 0.06-0.14 free space wavelength. A parametric study is presented. The proposed DRA is built and the characteristics of the antenna are measured. Very good agreement between numerical and measured results is obtained

A wideband trapezoidal dielectric resonator antenna with circular polarization

A new design of a circularly-polarized (CP) trapezoidal dielectric resonator antenna (DRA) for wideband wireless application is presented. A single-layered feed is used to excite the trapezoidal shaped dielectric resonator to increase resonant frequency and axial ratio. Besides its structure simplicity, ease of fabrication and low-cost, the proposed antenna features good measured impedance bandwidth, 87.3% at 4.21 GHz to 10.72 GHz frequency bands. Moreover, the antenna also produces 3-dB axial ratio bandwidth of about 710 MHz from 5.17 GHz to 5.88 GHz. The overall size of DRA is 21 mm × 35 mm, which is suitable for mobile devices. Parametric study and measurement results are presented and discussed. Very good agreement is demonstrated between simulated and measured results

A novel equivalent definition of modified Bessel functions for performance analysis of multi-hop wireless communication systems

A statistical model is derived for the equivalent signal-to-noise ratio of the Source-to-Relay-to-Destination (S-R-D) link for Amplify-and-Forward (AF) relaying systems that are subject to block Rayleigh-fading. The probability density function and the cumulated density function of the S-R-D link SNR involve modified Bessel functions of the second kind. Using fractional-calculus mathematics, a novel approach is introduced to rewrite those Bessel functions (and the statistical model of the S-R-D link SNR) in series form using simple elementary functions. Moreover, a statistical characterization of the total receive-SNR at the destination, corresponding to the S-R-D and the S-D link SNR, is provided for a more general relaying scenario in which the destination receives signals from both the relay and the source and processes them using maximum ratio combining (MRC). Using the novel statistical model for the total receive SNR at the destination, accurate and simple analytical expressions for the outage probability, the bit error probability, and the ergodic capacity are obtained. The analytical results presented in this paper provide a theoretical framework to analyze the performance of the AF cooperative systems with an MRC receiver

Dynamics of market share in the microfinance industry in Bangladesh

We discuss evidence that the microcredit industry in Bangladesh has seen emergence of large variations in the size of the microfinance institutions operating in the market-- on the one hand, there are large national-level MFIs, while on the other hand, small localized MFIs operating only within the confines of a small area. Data from a recent survey of Pathrail union in Tangail district, a seasoned place for microcredit, reveals that within the local market competition is becoming more and more intense over time between established national-level MFIs and newly emerging local-level MFIs for market shares in terms of loan amount as well as borrowed members. Data reveals that there is market segmentation where some borrowers and MFIs opt for a package of low interest rates tied with low amount of loan disbursed and some other borrowers and MFIs settle for a package of high interest rates tied with high amount of loan disbursed. A Tobit regression estimation of member market shares in village micro credit market shows that size of the MFI, years of operation in the village, average loan size, deposit interest rates, loan amount disbursed for unique loan purposes (i.e., housing loan) are key determinants in determining MFI shares of a village microcredit market.Microcredit; Market Share; Product and Provider Characteristics of Microcredit

A New Wideband Circularly Polarized Dielectric Resonator Antenna

A wideband and compact circularly polarized (CP) C-shaped dielectric resonator antenna (DRA) is presented. The proposed C-shaped DR is excited by a simple stripe line connected to a coplanar waveguide (CPW) feeding line. The C-shaped DRA is circularly polarized with 19% axial ratio (AR) bandwidth. It is found that the CP bandwidth can be expanded by using a narrow short circuit strip. The final design achieves CP with 50% AR bandwidth. The proposed circularly polarized DRA (CPDRA) with good radiation characteristics offers an impedance bandwidth of 58% between 3.45 and 6.26 GHz for VSWR ≤ 2. The proposed DRA is fabricated and tested. Very good agreement between simulated and measured results is obtained

Seasonal and extreme poverty in Bangladesh : evaluating an ultra-poor microfinance project

Microfinance is often criticized for not adequately addressing seasonality and hard-core poverty. In Bangladesh, a program known as PRIME was introduced in 2006 to address both concerns. Unlike regular microfinance, PRIME introduces a microfinance scheme that offers a flexible repayment schedule and consumption smoothing, as well as production, loans. It targets the ultra-poor, many of whom are also seasonally poor, with a severe inability to smooth consumption during certain months of the year. Besides providing loans, PRIME offers extension and training services. This paper uses a quasi-experimental survey design to evaluate PRIME against regular microfinance programs. The results show that PRIME is more effective than regular microfinance in reaching the ultra-poor, as well as the seasonal poor. PRIME also helps reduce seasonal deprivation and extreme poverty. Although the program has demonstrated its promise, it is too early to conclude whether the accrued benefits are large enough to contain both seasonal and chronic poverty on a sustained basis.Rural Poverty Reduction,Regional Economic Development,Food&Beverage Industry,Debt Markets

Political Economy and Rural Loan Recovery: An Example for Bangladesh

The rural loan recovery problem in developing countries is frequently analyzed from borrowers and institutional perspectives. But a frequently overlooked problem is that borrowers often are discouraged to repay or institutions are not aggressive enough to recover loans because of political interventions of the government into rural financial markets to derive the benefits of getting re-elected. Failure to address this dimension in recovery analysis may lead to an incorrect prescription of policies. This paper provides an empirical analysis of how political interventions affect rural loan recovery in Bangladesh. The government in Bangladesh intervenes into rural loan allocation and recovery indirectly through financial policies - interest exemption, loan targeting, interest rates - and directly through local political leaders and government officials. The intensity of direct intervention is expected to increase during an election period. Four variables - inflation rate, election years, interest exemption years, and bank type - were included in the model. The empirical results showed that election, inflation rate, and bank type affect the loan recovery negatively, and interest exemption positively