RF and microwave signals are very sensitive to noise -much more sensitive than high -speed digital signals. This means that you need to minimize the noise, bell, and reflection, and at the same time be careful to deal with the entire system.
Returning the signal with the least inductance -the ground floor below the signal will be easier to ensure this path.
Discipline matching is important. With the rise of RF and microwave frequency, the tolerance will become smaller. Generally, the PCB drive needs to be fixed, such as 50 ohms, which means that during the transmission and sending to the receiver, the drive outputs 50 ohms.
The transmission line that is curved due to wiring restrictions should use a curved radius that is at least three times larger than the central conductor width. This will minimize characteristic impedance.
It is necessary to minimize the return loss, whether it is reflected by the signal or the bell. There will always be a return path, but your design should guide it and prevent the return from multi -layer leakage through the PCB.