Agilent_ADS_2011_Load_Pull_官方设计指南

1 © Copyright Agilent Technologies, 2012 Enhancements to Agilent ADS’s Load Pull DesignGuide Andy Howard, 2/23/2012 After the ADS 2011.10 release, we have updated the Load Pull DesignGuide. We have added several simulation setups and re-organized the menus to make them easier to navigate. This document discusses what is new. This is the new menu structure: 2 © Copyright Agilent Technologies, 2012 This shows some of the selections under the main menu selections: The (Maury) – Find Optimal Load for Specified Output Power and the selections under Mismatch Analysis are new. 3 © Copyright Agilent Technologies, 2012 These are the rest of the menu selections, including the new ones under Mismatch Analysis: 4 © Copyright Agilent Technologies, 2012 The (Maury) – Find Optimal Load for Specified Output Power setup reads in measured load pull data and finds the optimal load (for maximum efficiency) for each target output power that you specify. This is the Find_Optimal_Load_For_Specified_Pout schematic: 5 © Copyright Agilent Technologies, 2012 This shows the results, after running an optimization: 6 © Copyright Agilent Technologies, 2012 Selecting Mismatch Analysis > Constant Available Source Power inserts a copy of the Load_Mismatch_Sweep simulation setup. This is for investigating how a device or amplifier’s performance degrades as the load VSWR (relative to an optimal impedance) and reflection phase are swept. This setup allows you to specify the optimal load impedance at the fundamental frequency, as well as the impedances at the harmonics. The available source power in dBm is fixed. 7 © Copyright Agilent Technologies, 2012 This shows the simulation results, which include output power, DC-to-RF efficiency, power dissipated in the device, transducer power gain and input return loss: You may select one of the simulated mismatch loads with marker m1, and all the black dots on the different plots correspond to this load. 8 © Copyright Agilent Technologies, 2012 Selecting Mismatch Analysis > Swept Available Source Power inserts a copy of the Load_Mismatch_Sweep_PSweep schematic. This is the same as above, except that it includes a sweep of the available source power at each mismatch load. This allows us to use interpolation on the swept output power data and get results that correspond to a particular output power. This shows the simulation results: 9 © Copyright Agilent Technologies, 2012 The results are “keyed” to the desired power delivered, that you select with marker desired_Pout_dBm. The data indicate that the desired output power is not reached for every mismatch load, and the performances vary substantially with the mismatch load. The Mismatch Analysis > Constant Power Delivered selection inserts a copy of the Load_Mismatch_Sweep_ConstPdel schematic. This is similar to the swept available source power simulation above, except that instead, the available source power is optimized, attempting to deliver a specified desired power to each mismatch load. Because the power gain varies so much with the mismatch load, it is not likely that the power delivered goal will be achievable for all mismatch loads. 10 © Copyright Agilent Technologies, 2012 This shows the simulation results for a power-delivered goal of 25-25.05 dBm: While this optimization approach should be faster than running a power sweep for each mismatch load, you do have to re-run the optimization for each different power delivered goal. A few notes have been added to the various load pull simulation schematics to remind users of changes they might want to make to the setups.