L band

About: L band is a research topic. Over the lifetime, 674 publications have been published within this topic receiving 4570 citations.

The business case for radio based AMR

Abstract: Low power radio enables the business case for automatic meter reading (AMR) to be satisfied. The Metscan system has developed for British Gas features a very efficient use of the radio spectrum. The author describes Metscan's Systematik 3000is product and the suitability of low-power radio for AMR.< >

L-band Superfluorescent Fiber Source

Abstract: An L band superfluorescent fiber source (SFS) is presented. The spectrum covers wavelengths from 1560 nm to 1615 nm. The L band SFS is constructed by a low power L band amplified spontaneous emission (L-ASE) seed source and a high power erbium-ytterbium co-doped fiber (EYDF) amplifier in double pass configuration. The output power of 0.72 W is obtained under 5.0 W, 980 nm pump power.

Design of Dual Band Microstrip Antenna at L-Band and S-Band Frequencies for Synthetic Aperture Radar (SAR) Sensors

Abstract: Synthetic Aperture Radar (SAR) is a remote sensing system using radar for high resolution image capture. The higher frequency used, the higher accuracy of the image detail that obtained, while, the lower frequency has a better image penetration capabilities. To combine these two advantages of the image result characteristic, SAR is designed to operate in two bands (dual-band). In this study, a dual-band antenna on 1.27 GHz (L-Band) and 3 GHz (S-Band) using slotted patch technique and proximity coupled feeding is designed. The material that used is the FR4 Epoxy dielectric with the relative permittivity of 4.6. As a result, the antenna operates at the frequency of 1.27 GHz with the return loss of -25.131 dB, VSWR 1.1201, and 19.9 MHz (return loss <= -10 dB) bandwidth. While the return loss of 3 GHz is -16.802 dB, VSWR 1.3381, and bandwidth (return loss <= -10 dB) 125.3 MHz

Present and future of L band SAR for small satellites

Abstract: In SAR-580 experiment using L/C/X band SAR mounted on Convair 580 was conducted for the first time in Japan. Based upon these results, L band HH was selected for SAR mounted on JERS-1. Later, PALSAR (full polarimetry) mounted on ALOS was developed and launched by H-IIA rocket. In FY 2013, PALSAR-2 mounted on ALOS-2 will be launched by H-IIA rocket. In this paper, present and future of spectral and technical issues of airborne and spaceborne L band SAR including small L band SAR to be resolved are presented.

Numerical analysis techniques for wideband amplifiers

Abstract: Increasing demands on the high capacity wavelength division multiplexed (WDM) transmission system now require newly developed transmission windows beyond the gain bandwidth supported by erbium-doped fiber amplifiers (EDFA) With the intensive development efforts on new rare-earth dopants and fiber nonlinearity (Raman process) for fast few years, wideband optical amplifiers now can support easily over 4-5 fold wider gain bandwidth than it was formerly possible with the conventional EDFAs Of various breeds for this application, there exist three distinct approaches near 150nm band, accessible in the commercial market These include: Thulium-doped fluoride fiber amplifiers (TDFA) for S+band (1450-1480 nm) and S band (1480-1530 nm), EDFAs for C band (1530-1560nm) and L band (1570-1610nm) and L band (1570-1610nm), Raman amplifiers with 100 nm's of gain bandwidth (with flexible location from S+ to L Band), and hybrid amplifiers with serial/parallel combinations of above techniques Even though there have been much increased experimental reports for all of these amplifiers, the complexity of the amplification dynamics from the number of involving energy levels and difficulty in measuring experimental parameters make it harder than ever to predict the performance of wideband amplifiers in general This lack of serious study on the analytic or numerical analysis on wideband amplifiers could cause the future impairments for the prediction and estimation of the amplifier performances for different applications, restricting the successful deployment of wideband amplifier based transmission systems In this paper, we present the numerical model and analysis techniques for wideband amplifiers (C/L band EDFA, Raman amplifier, and TDFA),along with their application examples