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Brokl, S. S.

Publications and source records attributed to Brokl, S. S..

12 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

Survey of current correlators and applications

With this summary an attempt is made to contact as many users as possible so as to provide summary data on correlation systems, both in use and as planned. Data on currently available very large scale integration (VLSI) chips and complete systems are included. Also, several planned correlator systems are described and summarized in tabular form. Finally, a description is given of the work being done in the Communications Systems Research Section on VLSI correlator chips and complete correlator systems.

Lahmeyer, C. R.↗
NASA NTRS1987

Radar Time-Base and Pseudonoise Generator

Long pulses effectively compressed by pseudonoise technique. Computer-controlled, polynomial-driven time-base and pseudonoise generator enables radar system to achieve range resolution of about 80 m with radar pulses of 1-s duration. Normally, unmodulated 1-s pulse has relatively coarse range resolution of several thousand kilometers. Radar system effectively compresses modulated pulse into one of 100-ns pseudonoise-modulating pulses. Intended primarily for use with interplanetary radar, time-base/pseudonoise concept proves useful in test instruments or in time-base correction for video recording.

Brokl, S. S.↗
NASA NTRS1985

Controller and interface module for the High-Speed Data Acquisition System correlator/accumulator

One complex channel of the High-Speed Data Acquisition System (a subsystem used in the Goldstone solar system radar), consisting of two correlator modules and one accumulator module, is operated by the controller and interface module interfaces are provided to the VAX UNIBUS for computer control, monitor, and test of the controller and correlator/accumulator. The correlator and accumulator modules controlled by this module are the key digital signal processing elements of the Goldstone High-Speed Data Acquisition System. This fully programmable unit provides for a wide variety of correlation and filtering functions operating on a three megaword/second data flow. Data flow is to the VAX by way of the I/O port of a FPS 5210 array processor.

Brokl, S. S.↗
NASA NTRS1985

A general monitor and control interface to the VAX UNIBUS by way of the DR11-C I/O port

The High Speed Data Acquisition System for the Goldstone Solar System Radar requires a number of interfaces for monitor and control functions for the special purpose data acquisition hardware. One common interface design is used. A large number of external control and monitor registers may be addressed and observed with this interface design, by using only three address locations on the UNIBUS and a standard DEC supplied input/output port. A broadcast control and status register is introduced which addresses any number of different units and registers.

Brokl, S. S.↗
NASA NTRS1984

Goldstone R/D High Speed Data Acquisition System

A digital data acquisition system that meets the requirements of several users (initially the planetary radar program) is planned for general use at Deep Space Station 14 (DSS 14). The system, now partially complete, is controlled by VAX 11/780 computer that is programmed in high level languages. A DEC Data Controller is included for moderate-speed data acquisition, low speed data display, and for a digital interface to special user-provided devices. The high-speed data acquisition is performed in devices that are being designed and built at JPL. Analog IF signals are converted to a digitized 50 MHz real signal. This signal is filtered and mixed digitally to baseband after which its phase code (a PN sequence in the case of planetary radar) is removed. It may then be accumulated (or averaged) and fed into the VAX through an FPS 5210 array processor. Further data processing before entering the VAX is thus possible (computation and accumulation of the power spectra, for example). The system is to be located in the research and development pedestal at DSS 14 for easy access by researchers in radio astronomy as well as telemetry processing and antenna arraying.

Deutsch, L. J.↗
NASA NTRS1984

Demodulator and Accumulator for the High-speed Data Acquisition System

In support of nonflight project data acquisition, a high speed data acquisition system was designed. The demodulator and accumulator modules at the heart of this system perform the detection and prefiltering of data which are then further processed by a floating point systems 5210 array processor. Block diagrams of the demodulator and accumulator modules are presented.

Brokl, S. S.↗
NASA NTRS1983

Polynomial driven time base and PN generator

In support of the planetary radar upgrade new hardware was designed to increase resolution and take advantage of new technology. Included is a description of the Polynomial Driven Time Base and PN Generator which is used for range gate coding in the planetary radar system.

Brokl, S. S.↗
NASA NTRS1979

Offset compensation for A/D converters

Analog-to-digital (A/D) converter eliminates dc offset in final digitized signal as well as in analog input by using digital feedback for compensation. Circuit could prove useful in data processing applications in which analog-format data are entered at high rates, as in point-of-sale data input systems.

Brokl, S. S.↗
NASA NTRS1976

The 512-channel correlator controller

A high-speed correlator for radio and radar observations was developed and a controller was designed so that the correlator could run automatically without computer intervention. The correlator controller assumes the role of bus master and keeps track of data and properly interrupts the computer at the end of the observation.

Brokl, S. S.↗
NASA NTRS1973

Numerical interactive controller

Device allows interaction of operator with data in computer central processor in order to shift frame of data in Cartesian coordinates and slew desired data into view. ''Cursor generator program,'' in conjunction with device, provides light pen with sufficient resolving power to identify any particular set of coordinates with single-cell accuracy.

Brokl, S. S.↗
NASA NTRS1973

Numerical computer peripheral interactive device with manual controls

A computer peripheral device is disclosed which includes a joystick whose displacement from a counter position along two axes X and Y in either a plus (+) or a minus (-) direction is sensed. The displacement magnitude in either direction controls the rate of clock pulses provided by a variable frequency clock. The clock pulses from the two clocks are accumulated in two separate counters, whose contents are displayed. The contents of the counters are suppliable to a computer to update the contents of specific cells which define the position of a cursor on a display which is under computer control.

Zygielbaum, A. I.↗