Solid-state radars and low maintenance over the entire system lifetime. With SSPA radars, installing the transmitter and receiver behind the antenna is possible, and specific components, such as expensive waveguide rotary joints and site-specific long waveguides, are unnecessary. By enabling more efficient weather radar design with better performance, SSPA radars achieve greater sensitivity at significantly lower operational costs over their lifetime. Furthermore, SSPA systems incorporate built-in redundancy to prevent single-point failures. With independent transmitters for horizontal and vertical channels, the system can operate in single-polarization mode in case a fault emerges in one of the channels. Each transmitter contains several parallel amplifier modules producing pulsed power, and each module contains several parallel GaN transistors in the final amplification phase of the signal, adding yet another level of redundancy in case one of the transistors fails. With long-lasting amplifiers, SSPA radars provide continuous, uninterrupted data availability. Solid-state electronics also enable unique runtime calibration. A sample of the transmit pulse is coupled to the receiver so the outgoing signals can be constantly measured, for continuous pulse-to-pulse calibration and near real-time correction for high-quality data. In addition to their reliability and continuity advantages, SSPA radars provide significant technical benefits that enable meteorologists to provide early warnings and better protect people and property. A key technique is pulse compression, which maintains high resolution while transmitting more energy for increased sensitivity. SSPA radars transmit long pulses that are compressed to achieve the required range resolution, boosting the energy on targets and enabling detection of weaker signatures such as snow or drizzle. SSPA systems also employ hybrid pulsing, alternating between long pulses for maximum range and short pulses that cover near range without gaps in coverage to maximize the useful range and detail. Unleashed from the constraints of tubes, SSPA radars are designed from a blank slate to optimize all parameters. SSPA transmitters enable a more compact architecture, helping to minimize signal loss, noise and interference for better data quality. While the advantages of SSPA radars represent the next generation of weather observation, complementary advances such as solar power are also expanding options for weather observation. Energy accessibility issues can prevent radars from being deployed in ideal locations to fill coverage gaps. In remote regions, solar-powered radar systems provide a self-sufficient solution. With long-lasting amplifiers, SSPA radars provide continuous, uninterrupted data availability” radar network with solar energy in action ABOVE: Ethiopia’s new weather grid power by deploying a solar-powered C-band radar system. The arid climate and complex topography make establishing consistent electrical infrastructure difficult in remote areas of Ethiopia. Power outages are common, which poses a challenge for operating radar systems that require reliable energy. To address this challenge, Vaisala engineered a turnkey solar power solution for the country’s new C-band radar installation that features an array of photovoltaic panels to harvest abundant sunlight and charge backup batteries to ensure constant uptime of the weather radar network. Even during prolonged overcast periods, the battery system stores sufficient backup power to run the radar for up to four days without sunlight. This innovative off-grid approach ensures that radar data is available whenever needed for weather monitoring and forecasting, enhancing early warning capabilities to keep communities across Ethiopia safe. While SSPA improve radar capabilities and sustainability, thoughtful implementations such as solar power expand where and how radar systems can provide life-saving insights. A sustainable future Advancing weather radar sustainability Vaisala To learn more, scan the QR code or visit: www.vaisala.com In Ethiopia’s mountainous terrain, Vaisala, a global leader in weather, environmental and industrial measurements, overcame unreliable After over half a century of relying on vacuum tube technology, the future of weather radars is undoubtedly solid state. SSPA radar systems are already commercially available and deployment is rapidly increasing as meteorological services upgrade aging magnetron and klystron networks. With their proven advantages in reliability, measurement performance and lifetime costs, SSPA radars are poised to become the new standard worldwide. Overcoming the limitations of tubes, SSPA radar systems deliver transformative benefits to forecasters and the communities they serve. Minutes matter when issuing weather warnings, so the advantages of solid state are too significant for weather services to overlook when seeking an upgrade. 52 • www.meteorologicaltechnologyinternational.com • April 2024