AD8346: SSB phase noise

Question I am concerned about the SSB Phase noise and how to improve the performance. Would you please help to give some advice on this issue? Answer When we say phase noise at transmit signal, it might be mainly originated from local, of course some portion would be from non-linearity(harmonics distortions..) of the modulator. But it is mainly discussed at local. As you can see below (figure 1), phase noise of local spreads the desired signal. So if the customer wants to get the phase noise performance mentioned below at Modulator output, a good local source is required. At modulator, Local feedthrough and Sideband suppression (USB at below graph) are main parameters. These LO leakage, sideband suppression and harmonics affect performance like EVM, ACLR. Baseband offset compensation can be used to reduce LO leakage. Amplitude and phase compensation can be used to improve sideband suppression. For this correction, please refer to the application note AN-1039. Figure 1 Figure 2