Dear all,

Can we generate typical sine/ square/ triangular waves at 3 GHz? **I DO NOT WANT MODULATED/ I-Q SIGNAL!! **Just like common 33500 series Arb WG, I want to generate pure wave forms of following-

- Sine/ triangular/ square @ 3 GHz
- Arbitrary signal wave for m@ 3 GHz
- Add 3 GHz WGN to my input signal

My assumptions/ limited knowledge is-

[From N5172B datasheet]

only gives ARB waveforms upto 60 MHz

**N5172B-403 Calibrated AWGN, Fixed Perpetual License**

only gives ARB waveforms upto 160 MHz with options 653, 655, and 657

**N5172B-303****Mu**ltifunction Generator

are used with composite modulation features in AM, FM/PM, and LF out.

Sine wave: 0.1 Hz to 10 MHz

nominal Triangle, square, ramp, pulse : 0.1 Hz to 1 MHz, nominal

**IT SEEMS HARDLY POSSIBLE IN SIGNAL STUDIO, SO CAN WE DO IT IN MATLAB? **

**BASICALLY , CAN WE GENERATE THE SAID BASE BAND WAVE FORMS @ 3 GHz? **

Hi Rasik,

In theory, the highest un-aliased frequency that an Arb can generate is 1/2 its sample rate. In reality the need for filtering means it's really more like 1/2.5. For a sine wave of 3 GHz you would need an Arb with a sample rate of 7.5 GHz. The triangle and square waves require much higher sample rate to generate the higher harmonics contained in those signals. The fidelity of the triangle, square or user waveform will in part determine the Arb Sample Rate you need.

The M8190A Arb has a maximum sample rate of 12 GHz. This would provide the 3 GHz frequency and one harmonic, 6 GHz. This means the sine wave would look great but the Triangle and square wave would be less than ideal.

The M8195A has a 65 GHz sample rate and would be able to provide many 3 GHz harmonics.

Creating a sine wave in MATLAB is pretty straight forward.

Frequency desired = Sample Rate * Cycles / Points

Where

Cycle - Number of cycle in the sine wave. Must be an integer value 1 or greater and less than points / 2.

Points - Number of points in the waveform. Must be an integer value. Must be something supported by the hardware. For the M8190A when running at 12 GHz the waveform points must be an integer multiple of 64.

Cycles must be an integer value if you want the waveform to wrap seamlessly. If cycles is not an integer and the waveform is repeated a glitch will appear each time the waveform repeats.

Hope this helps

Pete