The M9381A, with its excellent modulation quality at high output power, can be used at power levels up to +10 dBm or more depending on the standard with little degradation to
adjacent channel power ratio performance.
As evident in Figures 3 and 4, the application of digital predistortion yields a greater than 10 dB improvement in the
adjacent channel power ratio. Data was also collected for a two-carrier stimulus utilizing the same experimental conditions, signals and evaluation board.
Dedicated one-button measurements, including channel power,
adjacent channel power ratio, and occupied bandwidth, confirm the distortion level or channel power performance of an AMPS, TDMA, CDMA, or GSM transmitter.
However, the
adjacent channel power ratio (ACPR) of the Doherty amplifier is somewhat lower than for the reference design.
The filtering capability of the ISL5416 provides >100 dB of out-of-band filtering to address even the most aggressive 3G ACPR (
Adjacent Channel Power Ratio) specifications.
Next comes measuring the spurious emissions from the DUT, which requires looking at leakage into adjacent channels, such as
adjacent channel power ratio (ACPR).
Very good adjacent channel efficiency is obtained at -50 dBc
adjacent channel power ratio (ACPR), as shown in Figure 9.
The SE2522BL is capable of +23 dBm of linear output power at an
adjacent channel power ratio (ACPR) of -30 dBc.
These measurements include field strength, channel power, occupied bandwidth,
adjacent channel power ratio, carrier to interference ratio and interference analysis.
Root raised cosine (RRC) filtering is added to the
adjacent channel power ratio (ACPR) measurement window to meet the needs of engineers performing 3G WCDMA FDD conformance testing.
(2) Both are tested with a two-carrier WCDMA signal, and in both cases the amplifier needs to meet an IMD requirement of -37 dBc and an
adjacent channel power ratio (ACPR) of -40 dBc.
In the 802.11b mode, the SE2525L meets all
adjacent channel power ratio requirements at +23 dBm output power.
