carrier feed-through in ADRF6755 I/Q modulator
时间：04-04
整理：3721RD
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Hi
I use ADRF6755 for upconversion in DVB-T transmitter chain.
I/Q signal are outputs of DAC with frequency around 50MHz.
I have a problem with the carrier nulling and side-band suppression in the output of ADRF6755.
I follow the instruction of Analog datasheet to omit the LO and image in the output of ADRF6755 and obtain a set of calibration data for every channel.
but sometimes when to turn on my module see LO and image with different power. after re-calibrating IQ modulator see that I have exactly two set of calibration data for every channel that are true randomly.
I don't understand the source of this problem.please, help me!
I use ADRF6755 for upconversion in DVB-T transmitter chain.
I/Q signal are outputs of DAC with frequency around 50MHz.
I have a problem with the carrier nulling and side-band suppression in the output of ADRF6755.
I follow the instruction of Analog datasheet to omit the LO and image in the output of ADRF6755 and obtain a set of calibration data for every channel.
but sometimes when to turn on my module see LO and image with different power. after re-calibrating IQ modulator see that I have exactly two set of calibration data for every channel that are true randomly.
I don't understand the source of this problem.please, help me!
Poor layout design !?