The Tektronix CTS55 is a compact, modular digital radio tester engineered for GSM, DCS1800, and PCS1900 mobile phone service and repair. Manufactured by Rohde & Schwarz, it delivers user-friendly menu-guided operation through softkeys and clear navigation, supporting tasks from counter-level functional tests to module-level component diagnostics. The instrument executes fast automatic functional tests and detailed manual measurements via independent RF signal generation, synchronized receiver analysis, and comprehensive bit error rate evaluation.
Technical Specifications
RF Signal Generation
• Frequency bands: GSM, DCS1800, PCS1900
• Extended coverage: 900 to 995 MHz and 1800 to 1990 MHz
• RF output level: -10 dBm to -110 dBm (RF OUT1); -15 dBm to -75 dBm (RF OUT2)
• Modulation: Dummy burst with selectable midamble or unmodulated CW
• Built-in reference: TCXO standard; OCXO available (Option CTS-B1)
• Synchronization to GSM signals after frequency and power entry
Measurement and Analysis
• Peak, average, and ramp power measurements with >55 dB dynamic range for GSM ramp analysis
• Timing analysis referenced to P0 bit with transmit power correlation
• Frequency and phase error: graphical and numerical display
• Bit error rate (BER): successive measurements with automatic signal level reduction to user-defined BER limits for sensitivity determination
• I/Q spectrum measurement: carrier and sideband suppression verification
• Pulsed burst and CW midamble triggering for accurate signal capture
• SMS transmission and reception without explicit call setup; error reporting on transmission failure
Optional Capabilities
• Module Test Mode (Option CTS-B7): individual mobile phone module measurements, adjustments, and service mode operation with narrowband spectrum monitoring for I/Q modulator tuning
– Key Features
• Menu-driven softkey interface accessible to new users and service specialists
• Independent RF generator for GSM-specific signal requirements (AFC, RSSI adjustments)
• Dual RF outputs extend measurement and injection capability across power ranges
• Real-time receiver characteristic evaluation
– Typical Applications
• Mobile phone functional validation at service counters
• Module-level repair and component adjustment
• Transmitter power and timing compliance verification
• Receiver sensitivity and BER characterization
• I/Q modulator performance tuning
– Compatibility & Integration
Supports GSM, DCS1800, and PCS1900 mobile phones. RF signal generation and measurement synchronization enable direct phone connection for end-to-end system diagnostics.
