Adaptive Modulation Power Control Timing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In adaptive modulation schemes, changing to a higher modulation level without proper timing adjustment can lead to excessive transmission power, causing bit errors due to distortion in modulation waves, especially when the maximum transmission power is set for a lower modulation level.
Innovation Solution
A communication device and method where the transmission power control unit initiates power control before increasing the modulation level, ensuring that the transmission power does not exceed the maximum allowed, thereby reducing bit errors caused by distortion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the modulation level is increased to improve communication quality and data rate, then the transmission efficiency is improved, but the transmission power may exceed the maximum allowed power causing bit errors due to signal distortion
Solution Approach 1:
The transmission power control unit performs power control in advance before the modulation level is increased. This preliminary action ensures that the transmission power is adjusted to match the higher modulation scheme's requirements before the actual modulation change occurs, preventing power exceedance and resulting bit errors during the transition phase.
Solution Approach 2:
The system applies preliminary counter-action by controlling the transmission power downward before the modulation level increase. This preemptive power reduction counteracts the potential harmful effect of power exceedance that would occur if power control were performed after or simultaneously with the modulation level increase.
2Reliability
If the maximum transmission power is set for a lower modulation level to prevent bit errors, then the reliability is improved, but the transmission power is insufficient when switching to higher modulation levels reducing communication efficiency
Solution Approach 1:
The system dynamically adjusts the maximum transmission power setting based on the current modulation level. When a higher modulation level is selected, the maximum transmission power is increased accordingly. This dynamic adjustment allows the system to maintain reliability at each modulation level while enabling efficient use of higher power levels when needed for advanced modulation schemes.
Solution Approach 2:
The system changes the transmission power parameter in coordination with the modulation level parameter. By linking the maximum transmission power setting to the modulation level, the system ensures that appropriate power levels are available for each modulation scheme, optimizing both reliability and communication quality.
3Device complexity
If the timing of modulation level increase and transmission power control are not accurately adjusted, then the device complexity is reduced, but bit errors occur due to transient power exceedance
Solution Approach 1:
The transmission power control unit is designed to execute power control before the modulation level increase occurs. This timing arrangement eliminates the need for complex synchronization mechanisms while ensuring that power is appropriately controlled during the transition, preventing bit errors without increasing device complexity.
Data Source
AI summary
A communication device, which performs wireless communication according to an adaptive modulation scheme, includes a modulator that modulates data to be transmitted to generate a transmission signal, and a transmission power control unit that controls a transmission power of the transmission signal, wherein, when the modulation level increases according to the adaptive modulation scheme, the transmission power control unit starts control of the transmission power before the modulator increases the modulation level.