RF CURRENT



Welcome to RF Current, a weekly electronic newsletter focusing on Broadcast technical and F.C.C. related issues. This newsletter is part of The RF Page @ www.transmitter.com, a web site devoted to TV Broadcast RF engineering. For more information see the What is... guide to the R.F. Page site.

Issues are dated each Monday, although recently I've needed an extra day(week) or two to complete each issue. Articles may be posted earlier if time permits or if there is a major, breaking story.

<<< Back to December 18 - Issue 244

January 1, 2001 - Issue 245 Final Edition

FCC Adds Spectrum for Fixed and Mobile Services (Dec. 22)
The FCC has released a Report and Order on Amendment of Part 2 of the Commission's Rules to Allocate Additional Spectrum to the Inter-Satellite, Fixed, and Mobile Services and to Permit Unlicensed Devices to Use Certain Segments in the 50.2-50.4 GHz and 51.4-71.0 GHz bands.

The Report and Order said the FCC was providing a net increase of 2.27 GHz of spectrum allocated on a primary basis to the fixed and mobile services. The spectrum will be shared by Federal and non-Federal Government licenses. The spectrum from 51.4-52.6 GHz and 58.2-59 GHz is allocated for fixed and mobile services. The 64-66 GHz band is allocated for fixed and mobile services except for aeronautical mobile services. The Federal and non-Federal fixed and mobile service allocations in the 50.2-50.4 GHz and 54.25-55.78 GHz bands were deleted. The FCC anticipated the new spectrum will be used to connect base stations togethera and to connect with other systems, "backbone infrastructure for mobile services."

The FCC made the 57-59 GHz band available for use by Part 15 unlicensed devices, operating under the same technical rules as the existing part 15 unlicensed band at 59-64 GHz. The FCC Report and Order said the FCC expected this spectrum would be "useful for very high speed and/or high bandwidth communications communications over short distances and for networking backbone purposes in congested areas."

The 65-71 GHz band added for use by Federal Government and non-Federal Government inter-satellite services (ISS). The non-Federal Government ISS allocations at 56.9-57 GHz and 59-64 GHz were deleted. 64-65 GHz was allocated for Federal Government only ISS. Spectrum allocated to the Earth exploration-satellite (passive) and space research (passive) is being reduced by 4.65 GHz. NTIA found these allocations were unused and unneeded.

FCC Experimental Actions for 11/1 to 12/1/2000 (Dec. 21)
The FCC has released its monthly listing of Experimental Actions. This listing covers experimental applications granted during the period from 11/1/00 to 12/1/00.

The entry for experimental license WC2XMN, FHP Wireless, to use 2.4 MHz for testing and comparison of wireless LAN technologies in Cambridge, MA should probably say 2.4 GHz. Motorola received an experimental license to operate on 467.6875 MHz and 457.7125 MHz to test a vehicle locating application using FRS radios with GPS receivers nationwide. The only other item of interest was a grant to Sensor Technologies and Systems, Inc. to use 35.325-35.675 GHz for the test and development of roadway animal sensors in Yellowstone MT, Bend OR, Dubuque IA and Howe IN.

Refer to the FCC Experimental Actions list for details on all of the November grants.

CHIPS - NxtWave Introduces COFDM receiver and Improved VSB Demod (Dec. 20)
NxtWave Communications, known for its innovative 8-VSB receiver chips, announced the NXT6000, a single-chip COFDM receiver for the DVB-T DTV standard. The 64 pin NXT6000 chip includes an OFDM demodulator with Viterbi and Reed Solomon forward error correction and an integrated 10-bit analog to digital converter. It supports both high and low IF tuner architectures at either 36 MHz or 4.57 MHz. The chip includes an on-board controller, automatic data acquisition and reacquisition and digital timing recovery features, elminating the need for external components. "Minimal software" is required.

NxtWave said the NTX6000 supports all modes of the DVB-T standard, including hierarchical COFDM modes defined by ETSI, and is "the first dievice designed to meet the mandatory NorDig requirements for digital TV platforms in the Nordic region." Production quantities of the 64-pin LQFP packaged NXT6000 will be available in 1Q2001 at a price of $15 in quantities of 10,000.

NxtWave continues to improve its core 8-VSB product line with the introduction of the NXT2002, a second-generation multimode VSB/QAM receiver chip for DTV sets, PCs and digital set-top boxes. A NxtWave release said, "The NXT2002 combines best-in-breed performance and an extensive user-friendly feature set in the smallest package on the market today. The device demonstrates superior reception performance in the presence of multipath, phase noise, impulse noise, adjacent and co-channel interference for both terrestrial and cable environments."

NxtWave said the NXT2002 is the only VSB/QAM receiver chip to offer rejection of 0dB echoes. It uses an advanced sparse equalizer to provide better noise performance, enhanced multipath tracking and less jitter than conventional equalizers. The device can be configured to operate from a 25 MHz crystal or from an external 25 MHz clock source. The cost of external components is reduced through its on-chip integration of the direct IF sampling 10-bit ADC, AGC integrator, tuner control, all-digital symbol recovery and all-digital carrier recovery circuitry.

Matt Miller, president and CEO of NxtWave Communications stated, "The NXT2002 is testimony to NxtWave's commitment to the DTV industry. With our unique combination of market focus and innovative technology, NxtWave continues to drive the advancement of the industry with improvements to VSB design and performance." Robert Graves, chairman of the ATSC, praised NxtWave's efforts, saying, "The ATSC is delighted to learn of the introduction of NxtWave's second-generation high-performance VSB receiver chip. NxtWave's latest technical advancements exemplify the kind of innovation manufacturers are making in ATSC integrated circuits and receivers."

Production quantities of the NXT2002 in a 100-pin thin quad flat pack (TQFP) are scheduled for availability in 1Q2001 at a price of $20 each in 10,000 unit quantities.

For additional information these chips see www.nxtwavecom.com and the press releases NxtWave Communications Introduces NXT6000, New Product Launches Allow NxtWave Communications to Become Premier Developer of Top-Tier Integrated Circuits for both VSB and COFDM standards and NxtWave Communications Advances Digital Television Reception with Introduction of NXT2002 chip.

NxtWave also announced it was working with Alps Electric Co. Ltd, to develop the Alps TDLU7 single conversion tuner series reference design. This module will be available for volume shipment in 1Q2001, according to NxtWave. See NxtWave news release Alps and NxtWave Communications Partner on DTV Reference Design.

SCIENCE - NASA Says Sun Activity Near 11-year Cycle Peak (Dec. 21)
Scientists from NASA and NOAA say the Sun is near the peak of its 11-year cycle of activity. Scientists are using the largest coordinated fleet of spacecraft and ground observatories ever assembled to observe solar flares and predict the impact on Earth from powerful solar gusts. Dr. George Withbroe, Science Director for NASA's Sun-Earth Connection Program, said "This is a unique solar maximum in history. The images and data are beyond the wildest expectations of the astronomers of a generation ago."

NASA and NOAA coordinated activities to track an intense solar storm in mid-July nicknamed the "Bastille Day Event." Using data from ground based observatories and the Solar and Heliospheric Observatory (SOHO) satellites, scientists were able to anticipate the bright solar flare and associated energetic proton shower on July 13. NOAA forecasters are normally able to use the Advanced Composition Explorer (ACE) to provide advance notice of magnitude before the start of a geomagnetic storm, but the July solar shower blinded key ACE detectors.

The July storm flooded cameras and star-tracking navigation devices on several satellites with solar particles. The Japanese Advanced Satellite for Cosmology and Astrophysics (ASCA) was sent tumbling in orbit. Auroral displays were seen on Earth as far south as El Paso, Texas. According to the NASA Press Release NASA, NOAA Gain Unprecedented View of Angry Solar Cycle, power companies suffered geomagnetically induced currents that tripped capacitors and damaged at least one transformer. GPS accuracy was degraded for several hours. Dr. Ernest Hildner, director of NOAA's Space Environment Center in Boulder, CO, commented, "The July event was a surprise to some of our customers. They haven't seen this kind of activity for nearly a decade."

Additional information on the solar maximum may be found at http://www.gsfc.nasa.gov/GSFC/SpaceSci/sunearth/solarmax.htm.

OTHER Items of Interest

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