We present a novel method for desiging multiwavelength pumped fiber Raman amplifiers with optimal gain-flatness and gain-bandwidth performance. We show that by solving the inverse amplifier design problem, relative gain flatness well below 1% can be achieved over bandwidths of up to 12 THz without any gain equalization devices. This constitutes a substantial improvement in gain flatness compare...

The Gain flatness of EDFA (Eridium Dopedd Fiber Amplifier) plays a important role for WDM optical application. The purpose of this paper is to improve the gain uneveness for each channel in order to equalize the amplitude in a Wavelength Division Multiplexing (WDM) system .By using low pass Chebshev filter, tunning numerical aperature, fiber length and pump power we can improve the gain faltnes...

In the present paper, the problem of multi-pumping all Raman amplifier has been investigated to obtain a maximum flatness gain and increases the bandwidth of the cascaded Raman amplifiers over a wide range of optical signal wavelengths for long-haul ultra-wide wavelength division multiplexing (UW-WDM) transmission systems due to multi-pumping wavelengths and pumping power . Three cases are anal...

The effects of the pumping wavelength and their power on the gain flattening of a fiber Raman amplifier (FRA) are investigated. The multi-wavelength pumping scheme is utilized to achieve gain flatness in FRA. It is proposed that gain flatness becomes better with increase in number of pumping wavelengths applied. We have achieved flat gain with 0.27 dB fluctuation in a spectral range of 1475-160...

A Widely flatness gainbandwidth with double pass parallel hybrid fiber amplifier is experimentally demonstrated in this study. The proposed design combines serial erbium–Raman one branch and Raman the second branch. Multiple pump units a maximum power of 800 mW (250 1410 nm, 225 1480 325 1495 nm) are utilized. Pump recycling technique applied to achieve acceptable pumping efficiency. gain bandw...

A VHF (30MHz-300MHz) band digitally programmable low noise amplifier (LNA) has been implemented with a 0.25um standard CMOS process for VHF CMMB mobile TV tuners. Utilizing a T-match input network, input matching of more than a decade bandwidth is achieved across all gain settings. Adopting the multiple gated technique, gain flatness enhancement and capacitor reuse etc., the proposed LNA demons...

This paper presents a new approach for design of the log-periodic dipole array antenna (LPDA) based on using of different design parameters in the LPDA elements to control the antenna behavior. In the proposed procedure, the design parameters can control the value of forward gain over the operating frequency range, and also adjust the gain flatness. Furthermore, this design procedure can decrea...

A 90-nm wideband (1500-1590nm) optical amplifier consisting of a dispersion-compensated-fiber-based Raman fiber amplifier and a semiconductor optical amplifier with gain clamping and dispersion compensation is demonstrated for wide bandwidth amplification with gain flatness as well as dispersion compensation. 10Gb/s DWDM transmission over 100km conventional single-mode fiber link with low biter...