This discussion focuses on centering the carrier frequency for a baseband signal represented in IQ form. The method involves calculating the carrier offset and estimating the carrier bin, with the primary technique being the multiplication of IQ data by an exponential function of the carrier offset. This approach effectively shifts the carrier frequency to the desired position within the bandwidth. Additionally, the conversation touches on the concept of image rejection in IQ signals, which can be achieved through specific multiplication techniques without the need for additional filtering.
PREREQUISITESSignal processing engineers, RF engineers, and anyone involved in digital communications or modulation techniques will benefit from this discussion.
How can a baseband signal have a carrier? Is the “bin” one analysis frequency of many from a DFT?IKnowNada said:I have a baseband signal in IQ form. I have a method to calculate the carrier offset and estimate the carrier bin.
The base bandwidth or the RF bandwidth? Are you modulating or demodulating up or down converting frequency?IKnowNada said:I want to center the carrier to the middle of the bandwidth. How do I do so?
It depends on how you look at it but a Manchester Coded signal would normally be regarded as a baseband signal and yet it basically uses a clock that's at twice the data rate so the spectrum sits about a notional carrier. Manchester coding is a simple example of a coding system that has no DC component. Handy for passing through many kinds of transmission channel or recording system.Baluncore said:How can a baseband signal have a carrier?