Research On Power Amplifier And Linearization Techniques Based On TE-lTE And GaSs HBT Technology

In this paper, a Power Amplifier(PA) was designed using for mobile phone and other user equipments, which based on the project of Ga As Monolithic Microwave integrated circuit(MMIC) for the 4th generation mobile communications technology, TD-LTE.A high linear PA was achieved by two-stage amplifier, which core devices was GaAs HBT. Some fundamental theory was introduced in the paper, including relevant substrate materials of RF device, the model theory and modeling method of GaAs HBT device, and Process Design Kit(PDK). Meanwile, a sample of PDK was designed using the WIN’s HBT process parameters. A novel self-adaptive linear bias circuit was designed to maintain the input bias current, improve the performance of linearity, and controll the distortion caused by the phenomenon such as gain-compression, temperature drift, etc, after analyzed the PA linearization technology. Ultimately, the adjacent channel power ratio(ACPR) was improved 17 dB by a novel analog predistortion(APD) module in the 1st stage driving amplifier but the 2nd stage as the main amplifier.Stability of the PA was analyzed, during the designing process, after adding a RC parallel stable network in the base of the per-HBT decvice. The appropriate number of HBT as two-stage core devices of PA was selected by a method combining estimated and simulated. The maximum power matching method to increase the output power through the Load-pull technology in the 2ed stage amplifier. On contrary, the conjugate matching method was adopted to produce the biggest gain in the 1st driving amplifier. For producing lower matching loss, the passive inductors was simulated and designed in matching circuits. Ultimately, the performance of PA layout was measured by Cosimulation in the ADS Momentum 2.5 Dimension Electromagnetic Simulation Tools, which was carried out on the layout to simulate electromagnetic.The PA processing error was considered in the paper. Which communication frequency is Band 41, the Gain is equal or greater than 31 dB, the P1 dB is 30 dBm, the ACPR is-41dBc@29dBm output power, and the PAE is 46%@29dBm.