Signal simulation through Python scripts using shared memory for testing a C application
It is short and to the point. Looks fine.


  used via both Python scripts and application to interact with each other


You didn't describe the interaction, in English nor in code. Maybe the two sides routinely manipulate lots of data structures (1500 signals didn't quite sound like "a lot") that the other side uses less than 1% of the time, so your code or the multiprocessing support that ppperry highlighted would be appropriate. But the interaction is going to require condition variables or mutexes or higher level coordination such as queues. Since you've not specified the performance characteristics, I would just start with a TCP connection, or pub-sub, and go from there, see how things shake out. Localhost TCP offers very high bandwidth, and low latency. Profiling might reveal a need for shmem, but I'm skeptical, and it's better to cross that bridge after it's clear that you need to.