Qorvo Claims ‘Industry’s Highest Gain’ Pre-Driver for 5G Massive MIMO

Qorvo recently announced its QPA9822, the industry's highest-gain pre-driver for 5G massive multiple-input, multiple-output (m-MIMO) applications. 

 

Rendering of the QPA9822. Image (modified) used courtesy of Qorvo

 

M-MIMO systems have become a cornerstone of modern networks for achieving high data rates and connectivity. Amplifier technology is critical to enabling efficient and powerful signal transmission in these systems. Qorvo designed its new amplifier to manage wideband 5G NR instantaneous signal bandwidths and meet the modern challenges of m-MIMO applications.

 

New Wideband Driver Amplifier for m-MIMO

The QPA9822 is a high-performance wideband driver amplifier operating within a frequency range of 3.3 GHz to 4.2 GHz. The QPA9822 offers a gain of 39 dB at 3.5 GHz, making it a highly effective pre-driver for m-MIMO setups.

The amplifier is notable for its ability to handle high power levels while maintaining linearity, as evidenced by a 1-dB compression point (P1dB) of 28 dBm. In terms of power requirements, the QPA9822 operates at a voltage of 5 V and consumes 140 mA of current. It also features a noise figure (NF) rated at 4.5 dB.

 

Block diagram of a 5G sub-6-GHz massive MIMO application. Image used courtesy of Qorvo

 

A key feature of the QPA9822 is its internal matching to 50 Ω across its entire operational frequency band, simplifying the integration process into existing systems and ensuring consistent performance. Additionally, the amplifier includes a fast enable/disable function via the VEN pin, which enhances its operational flexibility in dynamic environments where quick response times are necessary.

Another notable aspect of the QPA9822 is its external bias control capability. This feature allows designers to fine-tune linearity and performance according to specific application requirements. 

 

What Is a Pre-driver?

In 5G applications, a pre-driver amplifier serves a role within the signal amplification chain, positioned as an intermediate stage before the final power amplifier (PA). Its primary function is to elevate the signal power to levels that can effectively drive the final PA without introducing substantial distortion or noise.

High linearity is an essential characteristic of pre-driver amplifiers, especially in 5G systems that utilize complex modulation schemes like quadrature amplitude modulation (QAM). Maintaining high linearity helps preserve signal integrity, preventing distortions that could result in data errors and degraded communication quality.

 

A standard RF signal chain. Image (modified) used courtesy of Samtec

 

In addition to boosting signal strength and maintaining linearity, pre-driver amplifiers also play a role in impedance matching between different stages of the amplification chain. Proper impedance matching is necessary to maximize power transfer and minimize signal reflection, which can adversely affect system performance. By ensuring that the impedance levels are compatible, pre-drivers contribute to the overall efficiency and reliability of the communication system.

Finally, pre-driver amplifiers help optimize the noise figure of the entire amplification chain. By amplifying the signal earlier in the chain, pre-drivers ensure that subsequent stages, particularly the final PA, do not significantly degrade the signal-to-noise ratio. 

 

Supporting 5G Deployment

Qorvo's QPA9822 is part of ongoing advancements in amplifier technology that are essential for the proliferation of 5G networks. By offering high gain, superior linearity, and robust performance across a wide frequency range, the QPA9822 addresses key challenges in signal amplification and integration. As 5G infrastructure continues to expand, advanced components like the QPA9822 become increasingly vital, paving the way for improved network efficiency and greater connectivity.