BPSK at MW frequency

I have a data stream @3Mbps, I want to modulate my carrier at 4GHz using BPSK scheme.

Kindly suggest,the right approach for doing this and references for such a high frequency digital modulation.

Just wanted to add that,the data is a CDMA code,which needed to be transmitted using a MW link.

one of these two approaches would work

Thanks biff44

I plan to use a mixer to generate bpsk signal.
I am mixing data stream with MW signal to do the job.

that will work, but there WILL BE significant LO leakthru. i.e. an unmodulated tone right in the middle of the output band. Some systems can not tolerate that.

The mixer approach is similar to the first method shown by you in the block scheme,what do you suggest in place of a mixer for 0 and 180 degree phase modulator.

what are the constraints for high bit rate BPSK?

Whether it's important,that carrier and data to be synchronised wrt same clock,or it's not essential?
If it's not synchronised,still we can get error free BPSK demodulation at receiver end?