AD9861 Datasheet, PDF (19/52 Pages) Analog Devices – Mixed-Signal Front-End (MxFE-TM) Baseband Transceiver for Broadband Applications

AD9861
Figure 58 to Figure 63 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 center four carriers are removed from the signal to observe the in-band intermodulation distortion (IMD) from the DAC output.
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6.0 6.2 6.4 6.6 6.8 7.0 7.2 7.4 7.6 7.8 8.0
FREQUENCY (MHz)
Figure 58. AD9861 Tx Path FFT, 256-Carrier (Center Four 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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6.97
6.98
6.99
7.00
7.01
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7.03
FREQUENCY (MHz)
Figure 61. AD9861 Tx Path FFT, In-Band IMD Products of
OFDM Signal in Figure 58
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6.06
6.08
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6.12
6.14
6.16
6.18
FREQUENCY (MHz)
Figure 59. AD9861 Tx Path FFT, Lower-Band IMD Products of
OFDM Signal in Figure 58
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7.81
7.83
7.85
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7.91
7.93
FREQUENCY (MHz)
Figure 62. AD9861 Tx Path FFT, Upper-Band IMD Products of
OFDM Signal in Figure 52
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FREQUENCY (MHz)
Figure 60. AD9861 Tx Path FFT of OFDM Signal in Figure 52,
with 1× Interpolation
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FREQUENCY (MHz)
Figure 63. AD9861 Tx Path FFT of OFDM Signal in Figure 52,
with 4× Interpolation
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