WIRELESS

The existing landscape of real-time communication often relies on traditional wire intercom systems which are characterized by high installation costs, complex wiring, and inherent flexibility, posing significant challenges for scalable deployment in dynamic environments. These limitations necessitate a modern, cost-effective, and easy-to-deploy solution that utilizes existing infrastructure. The primary aim of this project is to address this deficit by designing and implementing a functional, low-latency 4-channel Wi-Fi ( Wireless Fidelity) Local Area Network (LAN) based wireless intercom system capable of facilitating clear, full-duplex voice communication among multiple users. The system methodology centered on a decentralized, peer-to-peer architecture utilizing ESP32 microcontroller for its integrated Wi-Fi capabilities and dedicated I2S (Inter integrated sound ) digital audio interface. Audio quality was managed by pairing an INMP441 digital microphone with a MAX98357A digital amplifier, eliminating analog noise and circuit complexity. Crucially, communication over the LAN was executed using the User Datagram Protocol (UDP) instead of Transmission Control Protocol (TCP). This deliberate choice minimized packet overhead and connection management, which is essential for ensuring the reliable, low-latency data transmission required for real-time conversation. Testing confirmed the successful two-way voice transmission between all intercom units, with the system consistently demonstrating an end-to-end latency below the critical 150ms threshold required for human-perceptible real-time conversation. In conclusion, the project successfully validated the technical feasibility of leveraging commodity Internet Of Things (IoT) hardware for sophisticated communication tasks. The resulting system is a significantly more scalable and cost-effective alternative to legacy wired intercoms, demonstrating a framework for future development in affordable, high performance wireless communication product

In this paper, a wireless power transmission (WPT) using resonant magnetic coupling for mobile phone charger is presented. Solar energy was used as the energy source to address the scarcity of non-renewable energy sources and
tackles the constraints of wired charging technology such as lack of universal electrical standard, untidiness and inconvenience of wires and wires' wear and tear. The system includes PV panels and battery, oscillator, transmitting coil and receiving coil and rectifier. Proteus 8.1 was used to simulate before implementing in the hardware. The resonant magnetic coupling resonated at 800 kHz ± 10 kHz. The maximum distance to charge a mobile phone was 4 cm at 3.7 V. All the objectives are achieved within the limited time frame. The significance of the project can help to eradicate the use of wires and the need of power plugs. The future research includes the study of efficiency, coil design, system with multiple loads.