CARAVAN INTERNATIONAL CORPORATION
MODEL   803C
VHF/UHF Signal Acquisition and DF System

.                      • Integrated signal acquisition and DF system covers extended frequency range: 20 MHz - 3 GHz.

.                      • Wideband (12 MHz) digital signal processing and multichannel receiver system give exceptional speed and accuracy to find those elusive signals of interest (SOI) -- DF FIRST.

.                      • Modular, compact VME hardware architecture supports flexible implementation on fixed, transportable, or mobile platforms.

.                      • Unique antenna design for high mobility. Mobile stations can operate while moving. For increased range coverage, antenna is extended without the need for assembly.

.                      • Automatic network operation for fix triangulation. High speed wireless WAN communications between stations.

.                      • Integral Geographical Information System (GIS) provides a clear display of intercepts and target location on digital maps.

.                      • Effective support of both frequency control/clearing and frequency scanning mission phases.

                       • 1 GHz/sec fast scanning detection with SIMULTANEOUS DF of ALL detected signals at frequency channelization of 25 kHz.

.                      • Detection and DF of multiple modern frequency hopping and burst signals -- even multiple signals starting transmission simultaneously.
            • Full mission replay for:

            • post facto analysis with selective signal isolation using powerful set of interlinked graphical displays

            • post facto tri-angulations of all signals in full 20 MHz to 3 GHz band or all tasked sub-bands.

.                      • Client-Server architecture supports flexible operating modes: Local, Automatic, Fully Remote, and Multiuser/Network Operation.

.                      • Relational database engine maintains complete records on all intercepted SOIs, including date/time of intercept, frequency, measured signal parameters, measured line of bearing, and
            emitter location results when available.

.                      • Real-time signal display and parameter measurement provide accurate determination of modulation and signal identification.

 

SYSTEM OPERATING MODES Standard Mode

Focus is on the frequency control/clearing mission phase, including frequency-by-frequency detection, DF, and ITU-compliant signal characterization. Fixed Frequency Operation. Operator directly specifies the desired DF or signal measurement operations on a specific signal of interest. The selected measurement results are stored in the database and available for operator review.

DF Homing Operation. This operating mode is used in Mobile Units to “drive down” a transmitter of interest. The DF results are presented with respect to the front of the vehicle, and allow the driver to decide which direction to drive to approach the desired signal transmitter. The exact location of the Mobile unit is continuously updated by a high precision GPS, and the orientation of the vehicle with respect to North is measured by the built-in magnetic flux gate device.

Wideband DF Operation. System monitors up to 12 MHz instantaneous bandwidth, detects signal activity anywhere in the specified band, and performs DF. The results are presented in graphic form, as a two-dimensional azimuth versus frequency display.

Automatic Frequency Scan. The operator defines scan parameters, such as: multiple F1-F2 frequency ranges; exclusion frequencies; step size; signal activity threshold; and DF or signal measurement parameters. The system automatically scans the required frequencies, and upon detecting a signal, initiates the operator specified activity, such as: DF, signal measurement, digital audio recording. The measurement results are stored in the database and are available for operator display.

Automatic Scan from List. The operator can specify a set of discrete frequencies of interest for the automatic scan operation. System automatically performs operator specified activities and stores the results in the database.

Automatic Spectrum Monitoring. The operator specifies the required frequency ranges of interest, step size, signal activity threshold, and desired spectrum monitoring operations. The system automatically performs the specfied operations and stores the results in the database.

 

Fast Mode

Focus is on the frequency scanning mission phase, including wideband scanning with SIMULTANEOUS DF. All conventional and modern signals are detected, DFed, and geolocated in real-time and in post-facto analysis.

Wideband Scanning Detection with SIMULTANEOUS DF.

The operator specifies the frequency bands of interest. Using fast stepping wideband reception combined with DSP-based fine frequency channelization, all signals in the tasked bands are detected and SIMULTANEOUSLY DFed. Interlinked displays of DF reports include azimuth vs. time, azimuth vs. frequency, frequency vs. time, frequency histogram, and map-based direction from sensor location.

Modern Signal Detection and DF. Interlinked fast scanning detection/DF displays combined with powerful signal isolation capabilities enables real-time and post facto detection and DF of modern signals including frequency hopping and burst signals.

Full Mission Replay. All spectrograms and DF reports are stored in a high-speed database. All missions can be replayed with different graphical settings and signal selection/deselection criteria. Any station can merge data sets from multiple stations providing full post-facto geolocation of all signals in bands of interest.

 

System Operation Windows Interlinked Fast Mode Displays

.                       •               A powerful collection of interlinked displays that make it possible to analyze and geolocate multiple from a set of collected data representing many signals.

.                       •               Spectra and DF reports that have already been collected by the real-time system in a database are then extracted by an operator from that database into his workstation for display.

.                       •               The displays can also be used in real time as the data is going in to the database.

.                       •               Interlinked displays include spectrogram, frequency histogram, map with bearing rays from sensors, azimuth vs. time, and azimuth vs. frequency displays.

 

Geographic Map Display. Displays locations of Monitoring/DF stations, measured LOBs, and DF Triangulation fix of SOI. DF Polar Display. Displays measured LOBs as radial lines on polar plot, with reference to geographic North. DF Homing Display. Displays measured LOBs as radial lines on polar plot, with reference to the front of the Mobile vehicle. In the case of a single Mobile unit in motion, the geographic map display shows the successive positions of the Mobile unit, the LOBs measured from each location, and the fix result obtained by triangulation between selected LOBs. Azimuth vs. Time Display. Two-dimensional plot of azimuth vs. time. The azimuth-time correlation is used to identify and isolate co-channel interference, and to intercept and process modern digital modulations, such as TDMA/GSM. Azimuth Histogram Display. Displays measured LOBs on histogram plot, with reference to geographic North. Azimuth vs. Frequency Display. Two-dimensional plot of azimuth vs. frequency. Panoramic Spectrum Display. Real-time panoramic display of the signal, up to 12 MHz instantaneous display bandwidth, continuously updated. Waterfall Display. Real-time three-dimensional display of signal amplitude, versus frequency, and versus time. Signal amplitude is color coded shown as the third dimension, in perspective. Provides up to 12 MHz instantaneous display bandwidth, continuously updated. Allows wideband monitoring of time and frequency correlation between multiple signals, to help identify SOI in a crowded signal environment.

Spectrum Measurement Results. Displays spectrum characteristics in the selected frequency bands of interest. These measurements are used to identify traffic analysis patterns, and include the maximum, minimum, and median values of the following measurements:

.                       •               Channel occupancy vs. frequency

.                       •               Signal strength vs. frequency

.                       •               Message length vs. frequency

                        •               Channel occupancy vs. time of day

                        Signal Measurement Results. Displays the results of measurements of signal parameters of specified SOI, including the peak and average values of the frequency of operation, occupied bandwidth, signal strengths, and frequency separation. SOI Tabular Results. Tabular display of measured parameters of specified SOI, including: date/time of intercept, nominal frequency, measured signal parameters, measured line of bearing, and emitter location results. Mission-Tasking Panels. Graphical User Interface panels used by the operator to set-up signal processing tasks, including:

.                       •               Automatic Frequency Scan

.                       •               Automatic Scan from List

.                       •               Wideband DF Operation

.                       •               Automatic Spectrum Monitoring

 

Device Control Panel. Graphical User Interface panel used by the operator to control the settings of the receiver and the built-in digital recorder. It allows selection of receiver parameters, such as frequency, bandwidth, and detection mode, and includes an integral panoramic signal display to assist the operator in fine-tuning the receiver on the signal of interest.