AD9863

Rev. A | Page 15 of 40

Figure 34 to Figure 39 use the same input data to the Tx path, a 256-carrier OFDM signal over a 1.75 MHz bandwidth, centered at 7 MHz.

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

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FREQUENCY (MHz)

Figure 34. AD9863 Tx Path FFT, 256-Carrier (Four Center Carriers Removed)

OFDM Signal over 1.75 MHz Bandwidth, Centered at 7 MHz, with

20 mA Full-Scale Output into 60 Ω Differential Load

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Figure 35. AD9863 Tx Path FFT, Lower-Band IMD Products of

OFDM Signal in Figure 34

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Figure 36. AD9863 Tx Path FFT of OFDM Signal in Figure 34,

with 1× Interpolation

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Figure 37. AD9863 Tx Path FFT, In-Band IMD Products of

OFDM Signal in Figure 34

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FREQUENCY (MHz)

Figure 38. AD9863 Tx Path FFT, Upper-Band IMD Products of

OFDM Signal in Figure 34

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Figure 39. AD9863 Tx Path FFT of OFDM Signal in Figure 34,

with 2× Interpolation