AD9861 Datasheet, PDF (20/52 Pages) Analog Devices – Mixed-Signal Front-End (MxFE-TM) Baseband Transceiver for Broadband Applications

AD9861
Figure 64 to Figure 69 use the same input data to the Tx path, a 256-carrier OFDM signal over a 23 MHz bandwidth, centered at 23 MHz.
The center four 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 64. AD9861 Tx Path FFT, 256-Carrier (Center Four Carriers Removed)
OFDM Signal over 23 MHz Bandwidth, Centered at 7 MHz, with
20 mA Full-Scale Output into 60 Ω Differential Load
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22.6 22.7 22.8 22.9 23.0 23.1 23.2 23.3 23.4
FREQUENCY (MHz)
Figure 67. AD9861 Tx Path FFT, In-Band IMD Products of
OFDM Signal in Figure 64
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10.5 10.7 10.9 11.1 11.3 11.5 11.7 11.9 12.1 12.3 12.5
FREQUENCY (MHz)
Figure 65. AD9861 Tx Path FFT, Lower-Band IMD Products of
OFDM Signal in Figure 64
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33.5 33.7 33.9 34.1 34.3 34.5 34.7 34.9 35.1 35.3 35.5
FREQUENCY (MHz)
Figure 68. AD9861 Tx Path FFT, Upper-Band IMD Products of
OFDM Signal in Figure 64
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FREQUENCY (MHz)
Figure 66. AD9861 Tx Path FFT of OFDM Signal in Figure 52
with 1× Interpolation
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FREQUENCY (MHz)
Figure 69. AD9861 Tx Path FFT of OFDM Signal in Figure 52
with 4× Interpolation
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