Aeroflex 2050 Series Signal Generators - AEROFLEX - #5

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For the very latest specifications visit www.aeroflex.com Symbol Rate Mod Type min sym/s max sym/s Filter PSK, QAM 1900 34000 Nyquist/Root Nyquist PSK, QAM 1900 25000 Gaussian FSK, 1900 25000 Nyquist/Root Nyquist FSK, GMSK 512 25000 Gaussian OQPSK 1900 16000 All filters Symbol source can be internal or external, internal symbol rate is adjustable in steps of 0.1 symbols/s. Symbol rate must be within 2% of external symbol rate to maintain modulation accuracy. Generic Modulation types Can select PSK, Differential PSK, Differential Phase Offset PSK (i.e ð/4DQPSK), Time Offset QPSK, QAM, GMSK and FSK. The number of bits per symbol can be selected from 2 to 8 for QAM, 1 to 3 for PSK and 1 or 2 for FSK systems. RF Channel Filters Root raised cosine, raised cosine or Gaussian. Filter bandwidth can be selected as follows: Raised cosine or root raised cosine for á from 0.2 to 0.8 in 0.01 steps. Gaussian 3 dB bandwidth from 0.4 of the symbol rate (0.2 of symbol rate as IQ baseband filter) up to a maximum of 22.6 kHz. Pre-defined Modulation Types The following can be selected: Mod Type System ð/4 DQPSK ADC (DAMPS), PDC (JDC), TETRA, TFTS, APCO25 GMSK GSM, Mobitex, CDPD, MC9, DSRR, MD24-192N/W, Modacom OQPSK Inmarsat M FSK POCSAG, CITYRUF 4FSK ERMES, APCO25 8DPSK VDR (VDL) Modulation Accuracy At the decision points with the envelope input at 1 V or disabled and filter above 0.25 for raised cosine filters and 0.3 for root raised cosine filters: • PSK & QAM <1.5% RMS vector error • NADC, PDC <1% RMS vector error (EIA, RCR 27A method) • GSM & CDPD <3° RMS phase error (typical) FSK/GMSK Frequency deviation can be set with 1 Hz resolution across the range 100 Hz to 20 kHz. Accuracy: <1% of set deviation. Modulation errors Modulation errors can be added to simulate: IQ skew from 0 to ± 20° in 0.1° steps IQ imbalance from 0 to ±10 dB in 0.1 dB steps Carrier leak from 0 to 10% in 0.1% steps Range of errors allowed is limited by the peak envelope power. Note: modulation errors are not available in either GSM or OQPSK modes. IQ Outputs Baseband IQ output signals available on the front panel at a level of 0.5 V p.d. nominal into 50 Ù. Burst control Available on the rear panel D Type connector. A logic 1 on the burst control turns the RF on over a time interval corresponding to 3 data symbols. Propagation delay is matched to the data path delay. Can be used with the Envelope input. Burst control is not available with GMSK and FSK modulation types. ON/OFF Ratio Greater than 80 dB. VECTOR MODULATION Provides for IQ modulation of the carrier output from an external source for carrier frequencies of 10 MHz to 1.35/2.7 GHz. Carrier Leakage and SSB Image Rejection Following self-calibration, the RF carrier leakage and SSB image rejection are typically 50 dB. Vector inputs IQ inputs on the front panel. The RF level requested is obtained with 0.5 V DC applied to one of the inputs. Input impedance is selectable between 50 Ù and 300 Ù. DC Vector accuracy For carrier frequencies up to 2 GHz: ±1% amplitude of FS. ±1° at FS. For carrier frequencies above 2 GHz: ±1.5% amplitude of FS. ±1.5° at FS. Vector bandwidth ±0.5 dB wrt DC for modulation frequencies up to 3 MHz. ±1 dB wrt DC for modulation frequencies up to 10 MHz and carrier frequencies up to 2 GHz. ±1.3 dB wrt DC for carrier frequencies up to 2.7 GHz. IQ MODULATION CALIBRATION The signal generator can calibrate the IQ modulator automatically. After a 0.5 hour warm up period the calibration remains valid for at least 3 hours over a temperature range of ±5°C. The instrument displays a warning if the calibration validity time or temperature range has been exceeded. Calibration is valid for both digital and vector modes. FADING SIMULATION Rayleigh and Rician fading can be simulated in both Vector and Digital modulation modes. Doppler speed can be entered from 0 to 200 Hz with a maximum ratio of 2:1 between direct and scattered speed. Path ratio can be set to ±50 dB. Note: Fading is not available in either GSM or OQPSK modes. ENVELOPE CONTROL The RF level can be varied by applying a control voltage to the envelope input in digital and vector modes. The input may be used to shape the rise and fall of an RF burst and simulate the effect of varying RF levels being received from mobiles in TDMA systems. Applying 1 V gives the set RF level and 0 V suppresses the carrier. Linear range Greater than 30 dB. Linearity typically better than 0.5 dB at –20 dBV (100 mV input).