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One common approach is to use the sum of multiple LFSR sources to generate a random variable with a Gaussian distribution. The central limit theorem states that the sum of a large number of independent and identically distributed random variables (such as the outputs of independent LFSRs) tends towards a Gaussian distribution.   But what is the Central Limit Theorem? by 3Blue1Brown In this tentative design I used an Altera MAXII CPLD and an analog resistive adder. Note that the resistor ladder circuit will produce binary values that are discrete , so the resulting Gaussian noise will also be discrete rather than continuous. The central limit theorem states that the sum of a large number of independent and identically distributed random variables (such as the outputs of independent LFSRs) tends towards a Gaussian distribution. In practice, the number of LFSR sources required to achieve a good approximation of a Gaussian distribution depends on the size of the LFSRs and the de...

The  osmo-fl2k project  shows how to use an USB 3.0 VGA adapter as SDR transmitter.  Many thanks to Steve Markgraf. He presented it at OsmoDefCon 2018  https://youtu.be/VRvLVjLQSaw  . I made a  console tool named fl2k_noise that generates white noise in the full HF band. You can buy Fresco Logic 2000 based USB to VGA adapter in Aliexpress or Ebay for some 5-10$ price. See more info and the adapter scheme on  https://gitlab.hamburg.ccc.de/MarBle/fl2k-liberation/tree/assets The adapter was laying in my shack when I decided to test it as wide band (white) noise generator for HF band.  I selected an old VGA to VGA cable quite long and flexible and I cut it in the middle,  I cabled it as in the following scheme to adapt the 3 *75 Ohm input to the 50 Ohm output. The capacitors remove the VGA DC component and in case isolates the ANT bias tee of the receiver. The tentative code is in my repository  https://github.com/ik1xpv/fl2k_win ...