Combined Processing of
GPS, GLONASS, and SBAS
Code Phase and Carrier Phase Measurements
Lambert Wanninger, Stephan Wallstab-Freitag
Geodetic Institute, Dresden University of Technology, Germany
Abstract: This document explains how the Cupertino (MAXREFDES5#) subsystem reference design meets the higher resolution, higher voltage,and isolation needs of industrial control and industrial automation applications. Hardware and firmware design files as well as FFTs andhistograms from lab Measurements are provided.
A complete design for a data acquisition card for the IBM PC is detailed in this application note. Additionally, C language code is provided to allow sampling of data at speed of more than 20kHz. The speed limitation is strictly based on the execution speed of the "C" data acquisition loop. A "Turbo" XT can acquire data at speeds greater than 20kHz. Machines with 80286 and 80386 processors can go faster than 20kHz. The computer that was used as a test bed in this application was an XT running at 4.77MHz and therefore all system timing and acquisition time Measurements are based on a 4.77MHz clock speed.
The C500 microcontroller family usually provides only one on-chip synchronous serialchannel (SSC). If a second SSC is required, an emulation of the missing interface mayhelp to avoid an external hardware solution with additional electronic components.The solution presented in this paper and in the attached source files emulates the mostimportant SSC functions by using optimized SW routines with a performance up to 25KBaud in Slave Mode with half duplex transmission and an overhead less than 60% atSAB C513 with 12 MHz. Due to the implementation in C this performance is not the limitof the chip. A pure implementation in assembler will result in a strong reduction of theCPU load and therefore increase the maximum speed of the interface. In addition,microcontrollers like the SAB C505 will speed up the interface by a factor of two becauseof an optimized architecture compared with the SAB C513.Moreover, this solution lays stress on using as few on-chip hardware resources aspossible. A more excessive consumption of those resources will result in a highermaximum speed of the emulated interface.Due to the restricted performance of an 8 bit microcontroller a pin compatible solution isprovided only; the internal register based programming interface is replaced by a set ofsubroutine calls.The attached source files also contain a test shell, which demonstrates how to exchangeinformation between an on-chip HW-SSC and the emulated SW-SSC via 5 external wiresin different operation modes. It is based on the SAB C513 (Siemens 8 bit microcontroller).A table with load Measurements is presented to give an indication for the fraction of CPUperformance required by software for emulating the SSC.
This application note provides step-by-step instructions on how to recreate a Tri-Mode Ethernet(TEMAC) performance testing system using the ML405 board and MontaVista Linux 4.0. Thisapplication note shows how to set up a simple EDK Base System Builder system on the ML405Evaluation Platform and run performance tests. The network architecture for the test isdescribed. A system is built and downloaded into the FPGA. A MontaVista Linux kernel isconfigured, built, and downloaded into the ML405 Evaluation Platform. The instructions forobtaining and setting up the software used to perform the Measurements, netperf, are given.
This document is a quick reference to some of the formulas and important information related to optical technologies. It focuses on decibels (dB), decibels per milliwatt (dBm), attenuation and Measurements, and provides an introduction to optical fibers.
Abstract: Many modern industrial, medical, and commercial applications require temperature Measurements in the extended temperature rangewith accuracies of ±0.3°C or better, performed with reasonable cost and often with low power consumption. This article explains how platinumresistance temperature detectors (PRTDs) can perform Measurements over wide temperature ranges of -200°C to +850°C, with absolute accuracyand repeatability better than ±0.3°C, when used with modern processors capable of resolving nonlinear mathematical equation quickly and costeffectively. This article is the second installment of a series on PRTDs. For the first installment, please read application note 4875, "High-Accuracy Temperature Measurements Call for Platinum Resistance Temperature Detectors (PRTDs) and Precision Delta-Sigma ADCs."
This package implements a Kalman filter as described in the
paper "A Statistical Algorithm for Estimating Speed from Single Loop
Volume and Occupancy Measurements" by D. J. Dailey.
