Why can't we use WiFi and a hotspot at the same time?

Any wireless device has antennas that serve as the communication endpoints.

That is the antennas are responsible for transmitting and receiving data. When your phone is in the hotspot mode it acts as a base station. In other words it is in the transmission mode (Tx) for wifi.

To be able to receive the signal at the time you're transmitting you need at least two wifi antennas. If your mobile has it you can do it. If it does not then you can't.

One of the reasons I think phone and chip designers try to limit the number of antennas is that they consume quite a lot of power. You want to maximize the battery life and minimizing the number of operational antennas is one way to do it.

As an OS android which is built on linux kernel has no limitation that prevents any device from transmitting at receiving at the same time. The limiting factor is the hardware.

Comments

Why does collapsing a bubble with a sound wave produce light?

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WeWork India Sustainability Summit 2025 Tackling Technical Challenges in Green Building Innovation

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Can you compress water and turn it solid?

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Is there a future for materials science students in tribology?

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What IMC 2025 Revealed About the State of Telecom

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Unlocking the Potential of Carbon for Long-Distance Electrical Transmission

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Do electrons really flow as a beam in cathode ray tubes?

Abstract: It is generally well accepted that a beam of electrons flow from cathode to anode in a cathode ray tube. Taking pressure data from a variety of sources from CRT manufacturers’ data sheets to engineering documents of large hadron colliders we show through calculations that there is enough residual gas in these devices to form a conducting path from anode to cathode due to plasma formation. When high voltages are applied at the anode the gas is ionized and becomes a plasma forming a ‘wire’ between the two electrodes that causes conduction of energy. The objective of this brief note is to encourage scientists and engineers to re-investigate commonly accepted beliefs about vacuum tubes and develop new knowledge that can revitalize the field especially at a time when nano scaled vacuum channel transistors are being envisioned. Most vacuum tubes have operating pressures in the ultra high vacuum range. This is true for cathode ray tubes, vacuum tu...

Low energy fabrication of a high strength layered ceramic composite for high temperature oxidative environments

High temperature materials are required in various applications: in metallurgy, for making combustion chambers of internal combustion engines ,for the body of Stirling engines, for wall material of nuclear fusion reactors, for the body of Jet engines among a few. For such applications we need materials that can retain their strengths at elevated temperatures and can survive in an oxidative environment It is the second requirement which is more stringent. Although numerous metallic alloys have been synthesized that can sustain both high temperatures and oxygen attack they require complex processing steps On the other hand ceramics are good at resisting both oxygen attacks and high temperatures and are relatively simpler to fabricate but are limited by massive amounts of energy required. For example c/sic composites will perform well in demanding high temperature oxidative environments but require vacuum to be manufactured. The acheson process for the formation of sic is...

Force calculations on electron in vacuum tubes

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Manufacturing technique for layered carbon /ceramic composite for use in high temperature oxidative environment

We previously described a layered carbon glass material system that is different from c/sic , c/sio2 matrix composites in that it consists of a distinct C/C phase which is coated by an sio2 layer. https://akshatjiwannotes.blogspot.com/2024/12/low-energy-fabrication-of-high-strength.html This material system presents a distinct advantage in a high temperature oxidative atmosphere as the C/C matrix is protected by the oxidation resistant glass shield. Such a material can supposedly be synthesized in an open oxidative atmosphere. In this short note we will answer some questions such as What manufacturing technique will be used? How can silica particles be sintered on the substrate? How can adhesion between sintered particles and carbon substrate be ensured? What, if any ,sintering aids will be used? What would be the mechanical properties of the composite so formed? What level of heat treatment will be required? To make the composite only the minimum amount of heat ...

Notes by Akshat Jiwan Sharma

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