Visible light communication (VLC) is a promising solution to the increasing demands for wireless connectivity. Gallium nitride micro-sized light emitting diodes (micro-LEDs) are strong candidates for VLC due to their high bandwidths. Segmented violet micro-LEDs are reported in this work with electrical-to-optical bandwidths up to 655 MHz. An orthogonal frequency division multiplexing-based VLC system with adaptive bit and energy loading is demonstrated, and a data transmission rate of 11.95 Gb/s is achieved with a violet micro-LED, when the nonlinear distortion of the micro-LED is the dominant noise source of the VLC system. A record 7.91 Gb/s data transmission rate is reported below the forward error correction threshold using a single pixel of the segmented array when all the noise sources of the VLC system are present.

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By employing a GaN-based series-biased microlight emitting diode (µLED) array and orthogonal frequency division multiplexing modulation format, a high-speed free-space visible light communication system for long-distance applications has been demonstrated. The blue series-biased µLED array, which consists of 3×3, 20 µm-diameter µLED elements, presents promising performance with an optical power and -6dB electrical modulation bandwidth of over 10 mW and 980 MHz, respectively. Record data transmission rates have been successfully achieved at different free-space distances. Within 5 m transmission distances, over 10 Gbps data rates at the forward error correction (FEC) floor of 3.8×10 −3 are accomplished. Extending the transmission distances to 20 m, the data rates are maintained at the Gbps level at the FEC floor.

Visible light communication (VLC) using III-nitride light-emitting diodes (LEDs) offers many advantages such as license-free operation, high spatial diversity and innate security. In particular, micro-LEDs (µLEDs) are strong candidates for VLC due to their high modulation bandwidths. However, the low optical power of a single µLED is a key factor limiting VLC performance. In this work, we report an optimized series-biased µLED array to achieve higher optical power while retaining high modulation bandwidth for high-speed VLC. An example array consisting of 3×3 40 µm-in-diameter µLED elements is presented here. At a current density of 3200 A/cm 2 in direct-current operation, the optical power and small signal 6-dB electrical modulation bandwidth of a blue-emitting series-biased µLED array are over 18.0 mW and 285 MHz, respectively. The data transmission capabilities of this µLED array are demonstrated by using onoff-keying, pulse-amplitude modulation, and orthogonal frequency division multiplexing modulation formats over free space with the error-free data transmission rates of 1.95, 2.37 and 4.81 Gbps, respectively.

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