Aeroflex 2050 Series Signal Generators - AEROFLEX - #2

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The wide IQ bandwidth allows the generation of Direct Sequence Spread Spectrum signals as used in CDMA as well as QAM and OFDM signals as used in new broadcasting formats such as DAB (Digital Audio Broadcast). Precision radar Chirp signals can be simulated in conjunction with an Arbitrary Waveform Generator to test radar receivers. Digital Modulation In digital mode, the signal generator is able to produce a wide array of digital modulation types and in each case the user is free to modify the data rate and filter characteristics to suit individual application needs. This level of control and flexibility means that the 2050 series is fully prepared today for the digital formats of tomorrow’s narrow band digital radio communications equipment. For common standards, the 2050 is already pre-programmed to generate the required modulation format from a single key press and so aid ease of use. Proprietary schemes can be created and stored into non volatile user memories. Mod Type System ð/4 DQPSK NADC (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) Data rates up to 34 ksymbols/sec can either be generated internally from a pseudo random sequence generator or supplied externally as a serial or parallel data stream into a flexible digital interface. A burst control input allows TDMA or TDD bursts to be generated synchronously with the data. A separate analog envelope control input allows linear control of the RF level to simulate bursted modulation conforming to power time template and adjacent channel spectrum requirements. In digital mode the user can introduce defined errors to the modulation as skew, gain imbalance and carrier leakage, and so aid investigation of design limitations. Fading Simulation The built-in Rician and Rayleigh fading simulator with programmable path ratio and Doppler speed allows testing of receivers under ‘real life’ propagation conditions in which receivers must operate. The availability of fading simulation at the early design stages of new communications equipment simplifies the development of more robust designs and reduces the time taken for full compliance testing. Software Assisted Calibration All calibration and re-alignment procedures can be carried out without removal of the instrument covers and can be performed either manually or automatically via the GPIB. No internal adjustments are necessary; even the frequency standard is adjusted via the front panel or GPIB. During manual alignment full instructions are given on the instrument display. In digital and vector modes a self calibration system optimizes the performance of the vector modulator; a warning is displayed when environmental changes or elapsed time warrant a recalibration of the modulator. Electronic Attenuator An electronic attenuator option is available to meet demanding extended life requirements for repetitive switching, found in high volume production applications. SPECIFICATION GENERAL DESCRIPTION 2050 series signal generators have a large screen dot matrix display with softkey function selection which allows flexibility of operation. Hardkey and data entry key together with a rotary control knob are also provided. The output may be modulated using ÖM, FM, AM, IQ vector or complex digital modulation. Pulse modulation is optional. CARRIER FREQUENCY Range 10 kHz to 1.35 GHz (2050) 10 kHz to 2.7 GHz (2051) 10 kHz to 5.4 GHz (2052) In digital and vector modes the lowest frequency is 10 MHz and for 2052 the highest frequency is reduced to 2.7 GHz. Selection By keyboard entry of data. Variation by up/down keys and by rotary control. Indication 11 digits with annunciators. Resolution 0.1 Hz. Accuracy As frequency standard. Phase incrementing The carrier phase can be advanced or retarded in steps of 1.5° using the rotary control. RF OUTPUT Range (Analog mode) –144 dBm to +13 dBm Max guaranteed output above 2.7 GHz is +11 dBm. With AM selected, the maximum output level reduces linearly with AM depth to +7 dBm at maximum AM depth. Range (Digital or Vector mode) –138 to +6 dBm peak envelope power. RF level is defined with a PRBS modulation applied in digital mode or with 0.5 V applied to either the I or Q input in vector mode.