Prioritizing Uplink Signals Of A Radio Access Technology

What is this patent about?

’087 is related to the field of multi-carrier communication systems , specifically addressing power control in scenarios where a wireless device communicates simultaneously using different radio access technologies (RATs). This is relevant in modern cellular networks employing carrier aggregation and dual connectivity, where devices can utilize licensed and unlicensed spectrum bands, potentially managed by different base stations.

The underlying idea behind ’087 is to prioritize uplink transmissions based on the radio access technology when a wireless device's total transmit power is limited. The device determines if the combined power required for transmitting signals via different cell groups (each using a different RAT) exceeds its maximum transmit power. If it does, the device drops scheduled transmissions from the lower-priority RAT to ensure that the higher-priority RAT transmissions can proceed without exceeding the power limit.

The claims of ’087 focus on a base station transmitting maximum transmit power allowances for different cell groups, each using a different RAT. The claims also cover the base station receiving uplink signals from the wireless device, where the wireless device has dropped scheduled transmissions from the lower-priority RAT due to the total transmission power exceeding the device's maximum limit. The priority is pre-configured such that one RAT is considered more important than the other.

In practice, this invention allows a network to ensure that critical communications, such as those on a licensed band (e.g., LTE), are not compromised by less critical transmissions on an unlicensed band (e.g., LAA). The base station configures the wireless device with maximum power limits for each RAT. The wireless device then calculates its required transmit power for each RAT's uplink signals. If the sum exceeds the device's maximum power, the device selectively drops the lower-priority RAT's transmissions, ensuring the higher-priority transmissions proceed.

This approach differs from prior solutions by explicitly prioritizing uplink transmissions based on the RAT type when power limitations occur. Legacy LTE systems might simply scale down the power of all transmissions, potentially impacting the quality of service for critical communications. By dropping the lower-priority RAT's transmissions entirely, ’087 ensures that the higher-priority RAT maintains its intended power level, thereby improving the reliability and performance of those critical communications.