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Berner, J. B.

Publications and source records attributed to Berner, J. B..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2004

Future capabilities for the Deep Space Network

This paper will look at three new capabilities that are in different stages of development. First, turbo decoding, which provides improved telemetry performance for data rates up to about 1 Mbps, will be discussed. Next, pseudo-noise ranging will be presented. Pseudo-noise ranging has several advantages over the current sequential ranging, anmely easier operations, improved performance, and the capability to be used in a regenerative implementation on a spacecraft. Finally, Low Density Parity Check decoding will be discussed. LDPC codes can provide performance that matches or slightly exceed turbo codes, but are designed for use in the 10 Mbps range.

turbo code↗
NASA NTRS2003

Two-way ranging during early mission phase

The range of a deep space vehicle is commonly measured today using a sequential ranging signal that is transponded at the spacecraft. The noise performance and the uplink spectrum of this scheme are charaterized here.

tracking ranging↗
NASA NTRS2000

Deep Space Network turbo decoder implementation

A new decoder is being developed by the Jet Propulsion Laboratory for NASA's Deep Space Network. This unit will decode the new turbo codes, which have recently been approved by the Consultative Committee for Space Data Systems (CCSDS).

turbo decoder turbo code↗
NASA NTRS1994

The Block V Receiver fast acquisition algorithm for the Galileo S-band mission

A fast acquisition algorithm for the Galileo suppressed carrier, subcarrier, and data symbol signals under low data rate, signal-to-noise ratio (SNR) and high carrier phase-noise conditions has been developed. The algorithm employs a two-arm fast Fourier transform (FFT) method utilizing both the in-phase and quadrature-phase channels of the carrier. The use of both channels results in an improved SNR in the FFT acquisition, enabling the use of a shorter FFT period over which the carrier instability is expected to be less significant. The use of a two-arm FFT also enables subcarrier and symbol acquisition before carrier acquisition. With the subcarrier and symbol loops locked first, the carrier can be acquired from an even shorter FFT period. Two-arm tracking loops are employed to lock the subcarrier and symbol loops parameter modification to achieve the final (high) loop SNR in the shortest time possible. The fast acquisition algorithm is implemented in the Block V Receiver (BVR). This article describes the complete algorithm design, the extensive computer simulation work done for verification of the design and the analysis, implementation issues in the BVR, and the acquisition times of the algorithm. In the expected case of the Galileo spacecraft at Jupiter orbit insertion PD/No equals 14.6 dB-Hz, R(sym) equals 16 symbols per sec, and the predicted acquisition time of the algorithm (to attain a 0.2-dB degradation from each loop to the output symbol SNR) is 38 sec.

Aung, M.↗
NASA NTRS1990

Mechanically-Steered, Mobile Satellite-Tracking Antenna

Signal from satellite tracked in moving vehicle. L-band, mechanically-steered, medium-gain antenna part of prototype radio equipment mounted in vehicle to demonstrate concept of land-mobile/satellite communication system. Provides such services as mobile telephone, voice or alphanumeric dispatch, paging, position-location information, and low-rate data transmission, for users within continental United States and Alaska. Antenna rotated mechanically until it finds direction from which maximum signal comes. Rate sensors provide inertial frame of reference during acquisition, so antenna locks onto signal even when vehicle turning.

Bell, D. J.↗