Topic
L band
About: L band is a research topic. Over the lifetime, 674 publications have been published within this topic receiving 4570 citations.
Papers published on a yearly basis
Papers
More filters
18 Jun 1995
TL;DR: A multibeam digital beamforming (DBF) antenna, developed for a future mobile satellite communications system, is mounted on a vehicle for a receiving experiment in a mobile environment using a satellite signal in the L band.
Abstract: A multibeam digital beamforming (DBF) antenna, developed for a future mobile satellite communications system, is mounted on a vehicle for a receiving experiment in a mobile environment using a satellite signal in the L band. The multibeam is formed by 2-dimensional FFT signal processing. Automatic acquisition and tracking of an arriving signal are achieved by selecting a maximum beam out of the multiple beams in real-time.
11 May 1998
TL;DR: Two ICs have been implemented as part of a mobile digital satellite radio receiver that makes a superheterodyne frequency conversion from L band to 1.84 MHz IF, with a high level of integration, i.e only a SAW filter outside the chip.
Abstract: Two ICs have been implemented as part of a mobile digital satellite radio receiver. An RF front-end stage makes a superheterodyne frequency conversion from L band to 1.84 MHz IF, with a high level of integration, i.e only a SAW filter outside the chip. A fully digital channel decoder receives the IF signal from the RF front-end and converts it by means of an integrated 6-bit half flash A/D converter. Its main functions are a QPSK demodulator, a Viterbi decoder, a Reed-Solomon decoder, a deinterleaver and TDM extraction. The analogue input signal carrier is 1.84 MHz while the maximum chip frequency is about 10 MHz in order to optimize power consumption. Output data are transferred using a serial interface at a maximum rate of 128 kbit/s, The channel decoder is implemented using a five-metal layer CMOS 0.35 /spl mu/m process, complexity is 1.5 million transistors, dissipating 50 mW with die size of 23 mm/sup 2/. For the RF front-end, implemented in a 20 GHz bipolar process, die size is 16 mm/sup 2/, power consumption is about 200 mW, and includes on-chip low noise amplifier, 3.6 GHz oscillator and two PLL loops.
01 Jan 2016
01 Jul 1975
TL;DR: In this article, the authors used a 1.2 m (4 ft. diameter) parabolic dish antenna mounted on the flying bridge of a modern 15,690-ton, commercial-container ship.
Abstract: Extensive antenna-noise temperature measurements at 1.6 GHz (L-band) were made using a 1.2 m (4 ft. diameter) parabolic dish antenna mounted on the flying bridge of a modern 15,690-ton, commercial-container ship. Both in-harbor and at-sea radiometer measurements were made that indicated a steady background, antenna-noise temperature value slightly less than 70 degrees Kelvin (K) at elevation angles of 5 percent, and greater, at 1.6 GHz. A comparison of theoretical and measured values indicate excellent agreement within about 5K for at-sea data. These measurements are helpful to RF equipment designers of maritime, L-band shipboard terminals for operation with the two, geostationary, maritime satellites, Marisat-A and -B.