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Phase Noise
Phase noise results from small, instantaneous changes in the output frequency
("jitter"). It is seen as an elevation of the apparent noise floor near the fundamental
frequency and increases at 6 dBc / octave with the carrier frequency. The 33210A's
phase noise specification represents the amplitude of the noise in a 1 Hz
bandwidth, 10 kHz away from a 10-MHz carrier.
Quantization Errors
Finite DAC resolution (14 bits) leads to voltage quantization errors. Assuming the
errors are uniformly distributed over a range of ±0.5 least-significant bit (LSB), the
equivalent noise level is -86 dBc for a sine wave that uses the full DAC range
(16,384 levels). Similarly, finite-length waveform memory leads to phase
quantization errors. Treating these errors as low-level phase modulation and
assuming a uniform distribution over a range of ±0.5 LSB, the equivalent noise
level is -76 dBc for a sine wave that is 16K samples long. All of the 33210A's
standard waveforms use the entire DAC range and are 16K samples in length. Any
arbitrary waveforms that use less than the entire DAC range will exhibit
proportionally higher relative quantization errors.
Keysight 33210A User's Guide
Tutorial
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