From the Korean War until the mid-2000s, China’s entire air force and ground-based air-defence capability was heavily dependent on supplies of Soviet and later Russian equipment, specialists and training.17 However, with the rapid maturation and modernisation of the People’s Liberation Army (PLA), the People’s Liberation Army Navy (PLAN) and the People’s Liberation Army Air Force (PLAAF) under President Xi Jinping, China has begun to exhibit equipment and tactics which are distinct from Russian equivalents.18China has procured the Russian SA-21 and continues to import Russian missile and aircraft technology. It has also developed its own equivalent to the SA-20 (S-300), called the HQ-9.19 Essentially, the HQ-9 is a hybrid design based on a Russian SA-20 but with radar, seeker head and C2 elements heavily influenced by American and Israeli technology. The latter have been acquired through obscure channels but it is likely to involve a mix of cyber theft, conventional espionage and dual-use technology transfer.20 With a significantly more capable domestic micro-electronics industry than Russia, China has been able to rapidly reduce dependency on Russian radar and processing systems, fielding its own systems for early-warning and wide-area surveillance right down to missile seeker heads.
...Despite slightly inferior SAM technology compared to the latest Russian SA-21, the Chinese are now pulling ahead in terms of radar and sensor technology. They are also better placed to pursue true multi-spectral sensor fusion than Russia due to a much larger and more advanced domestic electronics industry. Advances in sensor technology are being supported by a creative and wide-ranging approach to new platform applications including fighter aircraft, AWACS, high-altitude UAVs and space-based systems.
As I've pointed out in previous threads, China's level of military technology has almost caught up to Russia's overall, and will surpass it in as little as nine years.