You can certainly do complementary codes. There are a few things you have to keep in mind when implementing them. You may know this already but I'll put it here for anyone reading the post.
You need multiple phase-coded waveforms which you will combine after. If you are using the radarTransceiver object, then you will have to change your waveform and matched filter between each pulse. Then after you finish your frame/dwell, you can add the pairs of pulses together and continue your processing steps for your application.
