Exploring the Maximum Power Transmission of Pico Cells and Antennas

Understanding the power transmission limits of pico cells and antennas is crucial for network architecture and design optimization. According to 3GPP TS36.104, version 15.8.0, a local base station (picocell) is limited to output a maximum of 24 dBm. This limitation is also subject to additional restrictions based on local regulations.

Regulatory and Technical Limits

The maximum power transmission in pico cells and antennas is not solely determined by technical specifications but also by regulatory constraints. Technical limitations, as set by 3GPP, prevent the transmission of more than 24 dBm for picocells. On the other hand, local regulations might further limit the power output to ensure safe and effective operation within specific geographic boundaries.

Dielectric Breakdown and Antenna Limitations

The dielectric breakdown of the antenna forms another significant barrier to increasing power transmission. In air, the breakdown voltage is approximately 3 kV/mm, which sets a hard limit on the practical power levels that can be used without risking damage to the antenna. Ceramics and plastics, though more resistant to breakdown, are prone to contamination, which can affect performance. Moreover, their loss tangents, which are measures of energy dissipation in the material, are generally worse than those of air. This further restricts the effective power that can be safely transmitted.

Frequency Dependencies and Antenna Design

The dimensions of an antenna are closely tied to its frequency operating range, a factor that impacts the maximum power it can handle. Higher frequencies require smaller antennas and thus are limited in the amount of power they can transmit compared to their lower-frequency counterparts. For example, high-frequency microcells may reach their power limits before low-frequency picocells.

Phase Arrays and Power Handling

Phase array technology provides a solution for handling higher power transmissions. By using multiple antennas, phase arrays can distribute the power across multiple elements, effectively allowing for a higher total power output without exceeding individual element limits. This technology is particularly useful in environments where the need for high power transmission is crucial.

Conclusion

While the maximum power transmission in pico cells and antennas is currently limited to 24 dBm by 3GPP standards, the practical limits are often lower due to dielectric breakdown, material contamination, and loss tangents. Frequency and design also play critical roles in determining the effective power that can be transmitted. Phase array technology offers a way to overcome some of these limitations, allowing for more power-efficient designs in high-power applications.

Keywords

pico cell antenna power maximum transmission