Researchers have developed a chip-sized photonic filter to separate signals from noise and manage interference in a crowded radio frequency spectrum, aiding efficient data transmission for 6G wireless communication.
6G technology aims to improve 5G by using millimeter wave and terahertz frequency bands to convey data faster. However, distributing signals over a broad frequency spectrum increases the likelihood of channel interference.
Researchers at Peking University have developed a chip-sized photonic filter to separate signals from noise and suppress interference across the full radio frequency spectrum. The device aids next-generation wireless technologies to convey data efficiently in a crowded signal environment. The microwave filter chip can enhance wireless communication like 6G, for faster internet, improved communication, and reduced costs and energy consumption.
Researchers aim to develop a small, low-power, cost-effective filter for widespread deployment to protect signal receivers from interference across the full radio frequency spectrum. Functions, size, bandwidth, or electrical component requirements limit previous demonstrations. Researchers simplified the photonic architecture of the new filter into four main parts: a phase modulator, a double-ring switch, an adjustable microring, and a photodetector. The phase modulator modulates the electrical signal onto the optical domain, while the double-ring switch shapes the modulation format. The adjustable microring processes the signal, and the photodetector recovers the radio frequency signal from the optical signal. The double-ring and microring work together to create the intensity-consistent single-stage-adjustable cascaded-microring architecture, which doesn’t require additional radio frequency devices for various filtering functions, simplifying the system composition.
Researchers tested the chip by loading a radio frequency signal and collecting the recovered signal with a photodetector. Simulating 2Gb/s wireless transmission signals and receiving processed signals with an oscilloscope, the researchers demonstrated the filter’s performance by comparing filtered and unfiltered results. The research found that the simplified photonic architecture has similar performance, less loss and system complexity compared to previous integrated microwave photonic filters, making it more robust, energy-efficient and easier to manufacture.
The researchers plan to optimize the modulator further and enhance the filter architecture to achieve high integration, low noise and a wide dynamic range.
Reference : Zihan Tao et al, Highly reconfigurable silicon integrated microwave photonic filter towards next-generation wireless communication, Photonics Research (2023). DOI: 10.1364/PRJ.476466