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More complex and effective mines are each fitted with their own sensor system. Although this makes the mines slightly more difficult to construct, such a minefield is not dependant on a single drone to run it and is hence more resistant to countermeasures.
The better mines are essentially tiny drone spacecraft, fitted with their own independent sensors and drive system, controlled by an artificial intelligence computer. The Federation Type 16 mine is an example of this type - it constantly surveys space around it to a radius of five light seconds, analysing anything which enters this zone and comparing it to a pre-programmed file of enemy vessel types. The entire minefield can be networked together, allowing them to share sensor information between them. If an enemy target enters the field the mines will determine which one has the best possible intercept solution; this mine will activate its micro impulse drive at the appropriate moment and track in on the target, detonating its warhead at the moment of closest approach. The Type 19 mine operates in a similar manner but the mines are fitted with a small warp engine to allow them to engage targets using warp drive. At this level the mine is essentially a photon torpedo capable of lying dormant for long periods.

The most recent development in Federation mine technology is the Type 21 mine developed by an engineering team on Deep Space Nine under Chief Miles O'Brien. At one metre in diameter this is one of the smallest mines in use by the Federation. It contains a photonic charge equal to several hundred grenades rather than a matter/antimatter charge, along with a micro impulse system and sensor system capable of scanning out to a radius of two thousand kilometres. This very limited range and destructive capability is more than offset by the use of both a cloaking device and a replicator system on the mines; when a target is detected the mines calculate the number required to destroy it, and allocate that number to the task. Once the target is destroyed the mines in that area latch onto the wreckage of both mines and target and use it in their on-board replicators to construct new mines. This allows the field to actually increase in size and density substantially whenever a target is attacked. This type of minefield is exceptionally difficult to clear; the use of a cloaking system on the mines means that an enemy can never be sure that every mine has been destroyed in a weapons barrage. Should only a handful survive to destroy another target, hundreds or even thousands more mines are quickly replicated and the field can be back up to full strength within hours. Such a minefield was deployed at the Bajoran Wormhole to block access by Dominion forces, triggering the Federation-Dominion war. The Dominion forces which captured DS9 at the outbreak of the war struggled several months to disable the minefield without success.