Patent ID: 8351876
Filing Date: 2013-01-08
Classification: H03F,H04B

Abstract:
1. A linearized transmitter having an amplifier which applies a nonlinear amplifier transform having a memoryless component and one or more memory components to a signal input to said amplifier, said linearized transmitter comprising: a look-up table (LUT) having an address input responsive to a first communication signal and having a multiplicity of data entries; a multiplier having a first input responsive to said first communication signal, a second input responsive to said data entries from said LUT, and an output which provides a second communication signal that corresponds to said signal input to said amplifier; and an adaptive control section having a first input responsive to a signal output from said amplifier, a second input responsive to said first communication signal and an output which updates said data entries, said adaptive control section being configured to implement a first continuous process control loop algorithm to calculate updated data entries for said LUT without performing complex conversions between Cartesian and polar coordinate systems and without performing division operations, and said adaptive control section being configured to cause said LUT data entries to adapt to said memoryless component of said nonlinear amplifier transform in accordance with a first tracking period; wherein said adaptive control section is further configured to implement a second continuous process control loop algorithm that compensates for influences of one of said memory components of said nonlinear amplifier transform in accordance with a second tracking period, said second tracking period being sufficiently fast so that said LUT data entries remain substantially unresponsive to said influences of said one of said memory components of said nonlinear amplifier transform.