AD9863

Rev. A| Page 14 of 40

Figure 28 to Figure 33 use the same input data to the Tx path, a 64-carrier OFDM signal over a 20 MHz bandwidth, centered at 20 MHz.

The two center carriers are removed from the signal to observe the in-band intermodulation distortion (IMD) from the DAC output.

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Figure 28. AD9863 Tx Path FFT, 64-Carrier (Two Center Carriers Removed)

OFDM Signal over 20 MHz Bandwidth, Centered at 20 MHz, with

20 mA Full-Scale Output into 60 Ω Differential Load

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Figure 29. AD9863 Tx Path FFT, Lower-Band IMD Products of

OFDM Signal in Figure 28

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FREQUENCY (MHz)

Figure 30. AD9863 Tx Path FFT of OFDM Signal in Figure 28 with

1x Interpolation

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FREQUENCY (MHz)

Figure 31. AD9863 Tx Path FFT, In-Band IMD Products of

OFDM Signal in Figure 28

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Figure 32. AD9863 Tx Path FFT, Lower-Band IMD Products of

OFDM Signal in Figure 28

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FREQUENCY (MHz)

Figure 33. AD9863 Tx Path FFT of OFDM Signal in

Figure 28 with 2x Interpolation