Rohde and Schwarz DDF200M Digital Direction Finder

The Rohde & Schwarz DDF200M is a digital direction finder engineered for precision radiolocation and interference hunting in maritime vessel traffic control environments. It employs the correlative interferometer DF method with advanced digital signal processing to deliver high accuracy and immunity to reflections. The system performs parallel direction finding across up to 32 maritime frequency channels simultaneously, with optional quasi-simultaneous DF capability on additional channels outside the maritime band. Adaptive interference cancellation is available, enabling co-location of maritime radiocommunications and DF antennas on the same mast. The DDF200M integrates with existing vessel traffic management systems via serial or TCP/IP interfaces and meets IALA recommendations for marine safety applications.

– Technical Specifications

• Direction Finding Method: Correlative interferometer DF method
• DF Accuracy: ≤ 1° RMS in reflection-free environment (typical: 0.5° RMS), includes lightning protection with R&S®ADD090
• Frequency Range: 118 MHz to 250 MHz (with R&S®ADD090); 118 MHz to 450 MHz (with R&S®ADD095)
• Parallel DF Channels: Up to 32 maritime frequency channels
• Scan Rate: 300 channels per second maximum
• Sensitivity: –120 dBm (typical)
• Antenna System: R&S®ADD090 VHF DF antenna with nine elements, 2-meter diameter above 150 MHz; R&S®GX090 antenna network
• Signal Processing: Advanced DSP for complex signal environments

– Key Features

• Parallel direction finding on up to 32 maritime channels with consistent accuracy across all frequencies
• Optional adaptive interference cancellation for co-located antenna systems
• Quasi-simultaneous DF on distress and non-maritime channels
• High sensitivity and reflection immunity through correlative interferometer design

– Interfaces & Integration

• Serial interface compatible with R&S®DDF100M
• Output to vessel traffic management systems via RS-232, USB, or Ethernet
• Antenna system powered via control cable from DDF200M or R&S®GX090C combiner network

– Typical Applications

• Vessel traffic management and radiolocation
• Interference detection and hunting in maritime communications bands
• Safety and efficiency enhancement in congested marine traffic zones