Energy Management and Power Management in Wireless Networks

This article discusses the basics of energy management and power management, along with techniques used in mobile and wireless networks. The primary goal is to extend the lifespan of wireless nodes, especially in situations where battery replacement or recharging isn’t feasible. This is increasingly crucial in today’s growing IoT-based and ad hoc wireless networks.

Many of these wireless nodes are designed as mesh nodes, communicating directly with each other as relay or route nodes. With no central coordinator or base station involved, extending the lifespan of these nodes is vital, as their failure can disrupt routing.

Energy Management

Energy management focuses on managing energy resources through strategies like:

• Limiting battery discharge
• Adjusting transmit power
• Proper scheduling of power management to save energy

These factors can significantly increase the lifespan of a wireless node or mobile device. Let’s explore these and other reasons for energy management in mobile and wireless networks.

• Recharge/Replacement Difficulty: Recharging or replacing batteries can be challenging, especially in war zones or during travel.
• Complex Functionalities: Mesh topologies mean nodes have more complex functionalities, including routing, leading to faster battery drain. This is common in ad hoc wireless networks, unlike infrastructure-based networks with a base station.
• Battery Size Constraints: The demand for smaller mobile phones has led to smaller battery sizes. This requires careful battery power conservation while keeping the battery size limited.
• Transmit Power Consumption: High transmit power consumes more battery. It also increases interference from nearby stations, limiting overall channel capacity. Using optimal power during transmission is recommended.
• Frequency Re-use: Optimal transmission power aids frequency re-use. The same frequency can be used in nearby cells for transmission and reception.

Power Management

Fig-1: Mobile phone internal hardware block diagram

Figure 1 shows typical hardware components in a GSM/CDMA/LTE mobile phone. It includes memory (RAM/ROM), display, keypad, CPU running applications, DSP running the wireless protocol stack, ADC/DAC, RF chip, Antenna, battery, SIM, mic, speaker, camera, etc.

• Power management minimizes power utilization by wireless systems or mobile hardware components like the CPU, RAM, ROM, and Display (LCD).
• Another approach involves incorporating low power consumption strategies into the protocol stack used by the mobile or wireless system. This is carefully considered during the protocol stack coding process.

Steps to Increase Smartphone Battery Life

The following steps can help increase smartphone battery life:

• Cool Environment: Keep the device in a cool environment, avoiding exposure to very high temperatures.
• Turn Off GPS: Disable GPS-based location tracking when not needed.
• Partial Charging: Avoid fully charging the battery.
• Brightness Level: Adjust brightness levels as needed for indoor and outdoor use, or maintain an optimal level.
• Scheduled Updates: Schedule application updates over Wi-Fi connections.
• Disable Unused Features: Keep Wi-Fi and Bluetooth OFF when not in use.
• Flight Mode: When in areas with no network availability, switch the smartphone to flight mode.