data rate and PN code

I have a question about the spreading sequence for CDMA. Normally, we use a PN code but imagine that we use a cosine wave combined with a PN code where the PN code has for length $$T * fs$$. With $$T$$ is the duration of the cosine wave, $$fs$$ the sampling frequency.

My question is about the duration: With a PN code (CDMA) the duration for 1 symbol is $$SF/B$$ with $$SF$$ the spreading factor and $$B$$ the bandwidth. But a combination with a cosine wave, the duration for 1 symbol is $$T$$ which the duration of the cosine wave or $$(T*fs)/B$$ with $$T*f_s$$ the length for the PN code.