Tech Brief: Wideband Fractional-N PLL Phase Noise Optimization Technology for Ka-Band LNB

With the widespread commercial use of ViaSat-3 and other high-throughput Ka-band satellites, DVB-S2X 256APSK high-order modulation has become mainstream in satellite communications, placing strict requirements on the phase noise performance of Ka LNBs. Traditional integer-N PLL architectures feature low frequency resolution and severe phase noise degradation, easily causing spectral spurs and signal jitter during wideband operation, which leads to high-order modulation demodulation distortion and limits high-speed satellite link performance.

To solve this technical bottleneck, the industry adopts wideband fractional-N PLL phase noise optimization technology for Ka LNBs. The hybrid Fractional-N and DDS phase-locked architecture breaks the limitations of traditional frequency locking, achieving ultra-fine 1Hz frequency resolution. This technology effectively suppresses high-frequency local oscillator spurs and optimizes near-carrier phase noise performance, eliminating signal jitter and spectrum offset during wideband scanning. Fully compatible with 17.6–26.7GHz full-band Ka reception, it perfectly meets high-order modulation demodulation standards, reduces link bit error rates, and greatly improves the transmission accuracy and link reliability of wideband Ka VSAT/FSS terminals for aviation and maritime high-speed satellite communication scenarios.