Modulation Switching via Demodulated Bit Error Rate Estimation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless communication systems face challenges in accurately determining the bit error rate (BER) for higher data rate modulation schemes based on signal quality metrics from lower data rate schemes, leading to potential errors and requiring large numbers of packets for reliable switching between modulation schemes.
Innovation Solution
A method and device that receive symbols using a first modulation scheme, demodulate them to determine signal quality, calculate an expected BER for a second modulation scheme, and decide whether to switch based on intermediate and final metrics, allowing for sequential calculation and reduced bit requirements for confidence in BER estimation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If modulation scheme switching is based on PER or RSSI from current lower data rate scheme, then switching decision can be made, but the estimation of BER at higher data rate modulation scheme is inaccurate
Solution Approach 1:
The patent performs preliminary demodulation of received symbols using the first modulation scheme to obtain demodulated bits before making switching decisions. This preliminary action enables calculation of signal quality metrics (BER, PER, RSSI) from actual demodulation results rather than theoretical estimates, providing accurate BER estimation for the second modulation scheme without requiring actual transmission at the higher data rate.
Solution Approach 2:
The patent uses demodulated bits as an intermediary between received symbols and switching decisions. By demodulating symbols and analyzing the quality of demodulated bits, the system obtains reliable signal quality metrics that accurately reflect the channel conditions for potential modulation scheme switching, resolving the contradiction between measurement precision and reliability.
2Reliability
If a large number of received packets are used to reliably determine switching, then switching accuracy improves, but the time required for switching decision increases
Solution Approach 1:
The patent calculates signal quality metrics (BER, PER, RSSI) from a relatively small number of demodulated bits obtained from current received symbols, rather than requiring a large number of packets. This partial action approach provides sufficient reliability for switching decisions without incurring excessive time delays, as the metrics are derived from ongoing demodulation operations.
Solution Approach 2:
The system uses the demodulation process itself to generate signal quality metrics needed for switching decisions. The demodulated bits from normal reception operations are utilized to calculate BER, PER, and RSSI, making the system self-sufficient for modulation scheme evaluation without requiring additional packets or extended measurement periods.
3Productivity
If switching is made to higher data rate modulation scheme, then data rate increases, but bit error rate may increase significantly
Solution Approach 1:
The patent implements feedback through calculation of BER, PER, and RSSI metrics from demodulated bits to evaluate the suitability of switching to a second modulation scheme. These feedback metrics provide real-time assessment of signal quality and predicted BER at the higher data rate, enabling informed switching decisions that balance productivity improvement with reliability maintenance.
Solution Approach 2:
The patent changes modulation scheme parameters (data rate and robustness) based on calculated signal quality metrics. By evaluating BER, PER, and RSSI from current reception and comparing against thresholds or predicted values for the second modulation scheme, the system dynamically adjusts modulation parameters to optimize both data rate and bit error rate performance according to current channel conditions.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
This disclosure provides systems, devices, apparatus and methods, including computer programs encoded on storage media, for receiving, by a first wireless device, symbols modulated using a first modulation scheme from a second wireless device, demodulating the symbols to obtain demodulated bits, determining a signal quality associated with the first modulation scheme based on a number of the demodulated bits, determining a value indicative of an expected bit error rate associated with a second modulation scheme based on the determined signal quality associated with the first modulation scheme, determining whether to switch to the second modulation scheme based on the determined value, and transmitting a message to the second wireless device to initiate a protocol exchange with the second wireless device to switch the modulation scheme to the second modulation scheme based on the determination.