5G Base Station: Digital Pre-Distortion (DPD)

5G Base Station: Digital Pre-Distortion (DPD)

The next fifth-generation (5G) wireless networks promise connection speeds and data rates that are 100 times faster than current networks, as well as much enhanced signal and connection quality. As wireless communication systems evolve, the necessity for linearity in Power Amplifiers becomes more difficult. The use of Radio Frequency (RF) power amplifiers with wideband signals, such as WCDMA utilized in UMTS, results in the development of out-of-band emissions known as “Spectral regrowth.” This work employs the Digital Predistortion approach to increase PA efficiency and linearity.

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DPD in conjunction with a power amplifier is created in MATLAB/SIMULINK utilizing the Memory Polynomial Algorithm. The developed algorithm was evaluated against a variety of test scenarios, and it was shown to have strong nonlinearity and good performance for memory polynomials of order 4 and 5, as well as non-linearity coefficients with linear output. The output of the previous and current inputs is produced using Memory Polynomial DPD. The benefit of DPD is that it produces a linear power amplifier with low distortion and high non-linearity.

DPD is a critical component of wireless communication systems that are used to increase the efficiency of power amplifiers. Power Amplifiers may be made significantly more efficient by decreasing the distortion caused by running them in their nonlinear areas. Wireless base stations that do not use CFR or DPD algorithms often have low efficiency, resulting in expensive operational and capital equipment costs.

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The Class AB LDMOS Power Amplifier will have a potential efficiency of 15-20% when employing WCDMA waveforms. Efficiency might rise by more than 30%, thanks to Crest Factor Reduction and Digital Pre-Distortion, which result in considerable CapEx and OpEx savings.

As a result, it is critical to examine DPD design since the more bandwidth there is, the more expensive it gets. Because everyone understands that 500 MHz is the core model for 5G, new DPD designs should be created on a regular basis. As a result, we offer a DPD design model that converts nonlinear PAs to linear PAs by adding a particular bandwidth range via a feedback loop.

When we feed the input signal into the proposed generation module, a restricted BB bandwidth is formed as a Predistorted signal that is confined to a particular bandwidth. The signal is then upconverted and fed into mm-wave PA, resulting in a decreased Tx bandwidth. As a result, only a portion of the distortion in the PA output will be compensated, and a band-pass filter will be used to suppress the remaining out-of-band distortion, which is quite modest.

As a result, we create a filter using PA that can be included in the PA output matching network. As previously said, the output PA has a limited bandwidth, which we feed into the feedback loop, which also has a limited bandwidth, and therefore we put input and output signals into the model extraction block.

The Faststream DPD core shortens implementation time by offering clients a high-performance DPD solution as a parameterizable core rather than one that must be modified by hand. Faststream DPD is also optimized for Xilinx FPGA implementation, resulting in a very small FPGA footprint and the lowest cost FPGA option available today. Faststream DPD IP now distorts and handles long-term memory effects encountered with Gallium Nitride (GaN) amplifiers, allowing customers to achieve great efficiency while fulfilling demanding spectrum emission mask (SEM) and Error Vector Magnitude (EVM) requirements at all power levels.

Benefits and Features

  • Two transmitters consume less than 100 mW of power, which is one-tenth that of comparable FPGA-based systems.
  • Allows for the use of a high-efficiency power amplifier (PA) to minimize system power consumption.
  • Complete development toolbox for reducing time to market.
  • A collection of tried-and-true power amplifiers from well-known brands.
  • Detailed user instructions, a full application program interface (API), and control graphical user interfaces (GUIs).

To know more about Digital Pre-Distortion. Get Solutions & Product Services of "5G Base Station". Connect with at info@faststreamtech.com