Wainwright Instruments Mobile Communication / 5G NR
- Band Pass Filters
- Manually Tunable Band Pass Filters
- Digitally Tunable Band Pass Filters
- Band Reject / Notch Filters
- Manually Tunable Band Reject / Notch Filters
- Digitally Tunable Band Reject / Notch Filters
- Monoplexers / Diplexers / Duplexers / Triplexers
- Absorptive Filters (BP/BR)
5G NR: Technology and Filter Requirements
5G NR (New Radio) is the fifth-generation mobile communications standard and defines a new era of connectivity with high data rates, low latency, and massive device networking. The standard operates in two main frequency ranges: FR1 (sub-6 GHz, 410 MHz - 7.125 GHz) and FR2 (mmWave, 24.25 GHz - 52.6 GHz). This broad frequency range places unique demands on RF filters, which must provide both ultra-wideband coverage for maximum capacity and narrowband, highly selective filtering for interference-free coexistence in densely packed spectrums. For manufacturers of network infrastructure and test equipment, filters with precise attenuation profiles, high performance, and thermal stability are therefore essential to meet the stringent 3GPP standards. Ensuring reliable performance throughout the entire product lifecycle is a top priority. While sub-1 GHz bands such as n28 (700 MHz) are used for nationwide coverage, mid-band capacity bands such as n41 (2.5 GHz) and n78 (3.5 GHz) as well as industrial high bands such as n79 (4.8 GHz) require extremely precise channel separation.
Typical Deployment Scenarios
5G filters from Wainwright are critical components for stable signal transmission in environments with the highest requirements for power handling and signal purity.
- 5G Base Stations (gNodeBs): High-performance filters are utilized in Macro-Cells for the n78 band (3.3--3.8 GHz) and in specialized radio heads for n258 (24.25--27.5 GHz) to suppress out-of-band emissions and maintain high signal purity.
- Private Campus Networks (Industry 4.0): Specially tuned filter solutions for industrial applications in the n77 range (3.7--3.8 GHz). They ensure local frequency exclusivity in factory halls by effectively suppressing interference from public networks or neighboring plants.
- Fixed Wireless Access (FWA): High-performance filters for stationary 5G routers (CPEs), primarily using the long-range n28 band (700 MHz). These filters ensure stable signal integrity over long distances, providing broadband speeds as a viable fiber optic replacement.
- Massive MIMO & Beamforming: Integration of highly selective filter components into active antenna systems, often operating in the n41 band (2.5 GHz). These enable precise signal routing and minimize mutual interference between antenna elements in complex 5G arrays.
- Coexistence & Spectrum Hygiene: Targeted filtering to suppress interference between 5G NR bands and existing services such as weather radar or satellite communication in the C-band. Our filters protect the receiver sensitivity of base stations from overloading.
- Test and Measurement Systems: Use of high-precision filters for characterizing 5G components under laboratory conditions and for compliance testing according to 3GPP. This includes validating components for the Asian n79 band (4.7--4.9 GHz) in development and manufacturing.
- Public Safety Networks (PPDR): Specialized filter solutions for the reliable integration of critical 5G communication into public safety networks, often in the 450 MHz to 800 MHz range. Highest reliability is required here to guarantee uninterrupted communication for emergency services even in congested radio environments.
- V2X & Automotive: Filter solutions for connected vehicle infrastructure, primarily operating in the n47 band (5.9 GHz). They support time-critical telemetry data, next-generation eCall services, and vehicle-to-everything (V2V/V2I) communication for autonomous driving functions.
Suitable Filter Categories for Mobile Communications / 5G NR
The 5G landscape utilizes globally different frequency bands focusing on a mix of low, mid, and high bands in the FR1 range. Wainwright Instruments offers optimized filter solutions for these demanding scenarios with high quality factors and thermal stability. Our portfolio covers common TDD bands as well as complex carrier aggregation scenarios. Each filter category is fine-tuned to the specific power and selectivity requirements of the respective 5G application.
Band Pass Filters
Our 5G Band Pass filters provide precise selection with extremely steep skirts for bands like n1 (2100 MHz), n28 (700 MHz), n41 (2.5 GHz), and n79 (4.8 GHz). These filters are specifically optimized for use in base station hardware, high-power amplifiers, and industrial 5G infrastructure applications. In infrastructure applications, our solutions deliver excellent selectivity with minimal insertion loss, maximizing the energy efficiency of the transmit power amplifiers. Compliance with strict spectral masks is ensured by our precision manufacturing, even at high power levels.
Manually Tunable Band Pass Filters
For 5G development applications in laboratory environments, we offer manually tunable Band Pass filters covering wide frequency ranges from 600 MHz to 6 GHz. Precise mechanical tuning via stable tuning elements allows for highly accurate adjustment of the center frequency for specific measurement setups in the sub-6 GHz range. They are ideal for identifying interference sources in the field or characterizing prototypes without costly hardware replacement. Technicians appreciate the robust construction and intuitive handling for troubleshooting directly at the radio mast. Our models are optimized for use in test racks and for portable field use.
Digitally Tunable Band Pass Filters
Electronically controllable filters support the requirements of modern SDR systems and automated 5G test benches in the n77 to n79 range. Via digital interfaces like SPI or I2C, filter curves can be adjusted in real-time to changing network parameters. This technology is essential for carrier aggregation testing and research in Dynamic Spectrum Sharing (DSS). Algorithm-driven adjustment enables a rapid response to frequency shifts in automated test environments. Our digitally tunable filters are optimized for use in reconfigurable test environments and measurement systems, combining digital control precision with high RF quality.
Band Reject Filters / Notch Filters
Our 5G notch filters serve to eliminate narrowband interfering signals that could impair base station sensitivity in the n78 range (3.5 GHz). They offer extremely deep stopband attenuation with negligible impact on adjacent 5G desired signals. This protects sensitive low-noise amplifiers (LNAs) from saturation by strong external signals like radar or satellite services. Especially in urban areas, they effectively prevent receiver overloading from strong neighboring signals. The high quality of our filters ensures clean separation even with minimal frequency spacing from the interferer.
Manually Tunable Band Reject Filters / Notch Filters
Frequency-tunable notch filters provide a flexible solution for interference suppression in complex 5G radio environments from n1 (2.1 GHz) to n78 (3.5 GHz). Manual adjustment of the stopband frequency allows for an immediate response to new interference sources without on-site hardware replacement. This is particularly relevant for test laboratories validating coexistence scenarios between 5G and other services. System integrators also use these filters in environments with varying interference sources to optimize radio quality locally. The robust mechanical design is optimized for frequent use in mobile test setups.
Digitally Tunable Band Reject Filters / Notch Filters
In intelligent 5G networks, digitally tunable notch filters enable an automated response to interference scenarios across the entire FR1 spectrum. Controlled by spectrum monitoring algorithms, these filters can dynamically mask interfering signals to ensure Quality of Service (QoS). They can be seamlessly integrated into automation concepts for radio optimization. This is particularly valuable in smart factories with varying interference sources from production. Remote controllability allows operators to adjust filter parameters centrally without sending technicians to the site.
Monoplexer / Diplexer / Duplexer / Triplexer
For 5G Advanced and complex Carrier Aggregation (CA), high-performance multiplexers are required to combine frequency blocks such as n28 (700 MHz) + n78 (3.5 GHz). Our solutions, like diplexers and triplexers, offer extremely low insertion loss and high isolation between ports. They are optimized for common 5G band combinations in the FR1 range and enable base stations to achieve maximum data rates through carrier aggregation. In FDD scenarios, our duplexers ensure reliable separation of uplink and downlink signals while maintaining high power handling. Precise tuning prevents crosstalk between bands and protects sensitive receiver paths in complex multi-band RRUs.
Absorptive Filters
Absorptive filters play a crucial role in high-power 5G transmit amplifier stages, particularly in the n41 range (2.5 GHz), to increase system linearity and longevity. They convert unwanted out-of-band signals and harmonics generated in the amplifier directly into heat. Instead of reflecting harmonics back to the amplifier, they are safely terminated in the filter, preventing reflection damage. This is critical for complying with strict spectral emission masks (SEM) in high-power infrastructures. Our absorptive filters are designed for high continuous power and are used in macro cells and test equipment to improve signal purity.