Amplitude-Shift Keying ASK Modulation | Agilent Technologies U2761A

2 Features and Functions

Amplitude-Shift Keying (ASK) Modulation

ASK is a form of digital modulation in which the modulating signal apply variations in the amplitude of a carrier signal. The amplitude of the carrier signal varies simultaneously with the modulating signal while phase and frequency remain constant. In other words, the carrier signal can be assumed as an on and off switch. You can configure the U2761A to “shift” its output amplitude between two preset amplitudes using ASK. The rate at which the output shifts between the two amplitudes is determined by the internal rate generator. An example of the ASK modulation waveform is shown in the following.

ASK rate

Figure 2-25ASK modulation waveform

To Select ASK Modulation

The U2761A allows only one modulation mode to be enabled at a time. The U2761A does not allow ASK to be enabled at the same time that sweep is enabled.

76	U2761A User’s Guide

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Agilent Technologies U2761A manual Amplitude-Shift Keying ASK Modulation, To Select ASK Modulation, ASK rate

Contents

User’s Guide U T I O N WA R N I N G Safety Symbols Use the device with the cables provided InstrumentPerformed by qualified personnels Environment Conditions Regulatory Markings Product Category Affixed product label is shown as below Declaration of Conformity Regulatory Information for Australia/New Zealand This Guide… Contents Output Control Sweep Time Index List of Figures Trigger output pulse List of Tables Xviii Getting Started Various features of the U2761A Introduction Top View Product at a GlanceProduct Outlook Bumpers Front View Fan Ventilation Pin backplane connector USB inletPower inlet Rear View 105.00 mm 175.00 mm 18.00 mm Product DimensionsDimensions Without Bumpers 25.00 mm 117.00 mm 180.00 mm 15.00 mm Dimensions With Bumpers41.00 mm Standard Purchase Items Initial Inspection Inspection and MaintenanceGeneral Maintenance Electrical Check Installation Installation and ConfigurationWith Agilent VEE Pro, LabVIEW, or Microsoft Visual Studio Check Your System Hard-disk space 1 GB Install the IO Libraries Suite Install the Module Driver Install the Agilent Measurement Manager T E Connect the Module to Your PC Proceeding Getting Started Select Ignore to disable the warning message Go to Start Control Panel and double-clickSystem Getting Started Verify Your Module Connection Send Commands To This Instrument IO Control will launch automatically when you start your PC Launch Your Agilent Measurement Manager T E Pin Backplane Connector Pin Configuration Description Chassis Installation Pulse Waveform Triggering Output Function Output ConfigurationIntroduction 1Output functions Function Limitation Amplitude Limitation Soft Front Panel Operation Waveform pattern selection Waveform parameters Remote Interface Operation Output Frequency2Output frequency range Function Limitations Duty Cycle Limitations Offset Voltage Limitations Output AmplitudeLimits Due to Output Termination Limits Due to Units Selection 4Panel view of the amplitude section DC Offset Voltage Limits Due to Amplitude VOLTageOFFSet offset Output Units Output Termination OUTPutLOAD ohmsINFinity Duty Cycle Duty Cycle Square WavesLimits Due to Frequency APPLy command automatically sets the duty cycle to 50% Symmetry Ramp Wave 9Ramp wave duty cycles Output Control 11Panel view of the output section Set Output Using Scpi Commands Example 1, To output a DC voltage Example 2, To output a Sine wave Example 4, To output a Ramp wave Pulse Waveform Pulse Period Pulse Width 13Panel view of the pulse width section Pulse Duty Cycle Duty Cycle = 100 ⋅ Pulse Width / Period Generate Pulse Waveform Using Scpi Commands Example To Select AM Amplitude Modulation AMModulating frequency AM depth Carrier Waveform 15Panel view of AM Carrier Frequency 3Carrier frequency for AM Default modulating waveform is Sine wave Modulating Waveform Modulation Depth Modulating Waveform FrequencyPeak into a 50 Ω load Generate AM Using Scpi Commands To Select FM Frequency Modulation FMModulating frequency FM deviation FMSTATe 0OFF1ON 4Carrier frequency for FM FMINTernalFUNCtion SINusoidSQUareRAMPNRAMpTRIangleUSER Frequency Deviation Generate FM Using Scpi Commands Modulating frequency Phase deviation Phase Modulation PMTo Select PM PMSTATe 0OFF1ON 5Carrier frequency for PM Default waveform is Sine wave Phase Deviation Generate PM Using Scpi Commands To Select FSK Modulation Frequency-Shift Keying FSK ModulationFSK rate Hop frequency FSKeySTATe 0OFF1ON FSK Carrier Frequency 6Carrier frequency for FSK FSK Hop Frequency 7Hop frequency Generate FSK Modulation Using Scpi Commands FSK Rate To Select PSK Modulation Phase-Shift Keying PSK ModulationPSK rate PSK deviation PSKeySTATe 0OFF1ON PSK Carrier Frequency 8Carrier frequency for PSK PSK Rate PSK Deviation Generate PSK Modulation Using Scpi Commands To Select ASK Modulation Amplitude-Shift Keying ASK ModulationASK rate ASKeySTATe 0OFF1ON 9Carrier frequency for ASK Generate ASK Modulation Using Scpi Commands ASK Rate To Select Sweep Frequency SweepFrequency Linear type Start frequency Stop frequency Start Frequency and Stop Frequency 28Panel view of sweep Sweep Mode Sweep Time Sweep Trigger Source Set Frequency Sweep Using Scpi Commands Triggering Trigger Source Choices Internal Triggering Manual Triggering External Triggering Trigger Rising edge shown Trigger Input SignalTrigger Output Signal Trigger out 500 μs Rising edge shown OUTPutTRIGger 0OFF1ON OUTPutTRIGgerSLOPe POSitiveNEGative Set Triggering Using Scpi Commands Arbitrary Waveforms To Create and Store an Arbitrary Waveform Select the Arbitrary waveform function Start waveform editing process Exiting the waveform editor Characteristics and Specifications Product Characteristics Operating Environment Product Specifications and Characteristics Waveforms Ramp, Triangle ±1% of settling ±5 mV ±10 mV @ Hi-Z Units Vpp, Vrms, dBm Resolution DigitsExternal frequency reference ±5 V across open circuit Modulation Sweep Characteristics 102 U2761A User’s Guide Index PSK United States Tel 800 829