A Perspective of Using Frequency-Mixing as Entropy in Random Number Generation for Portable Hardware Cybersecurity IP

True random number generator (TRNG) is a crucial component in security. In typical TRNGs, entropy comes directly from device noises. In this work, an improved method of using frequency-mixing as means for enriching entropy is implemented. A group of electromagnetic waves are mixed to create an irregular waveform that is then sampled to generate a random bitstream. Some part of the bitstream is fed back to the system for influencing the future frequencies of the sourcing waves, making it a chaotic system. The circuit-level support for this TRNG is the TAF-DPS (Time-Average-Frequency Direct Period Synthesis) technology. It can be digitally implemented, making the TRNG a portable IP. The merits of this TRNG include no need of special device, no post-processing, free of bias, programmable throughput, and hard-to-recognize spectrum. Those features make the TRNG suitable for a large array of applications, particularly for security in cyberspace. This TRNG is validated by a silicon chip on a 180 nm process, also on a FPGA.