Adaptive CRC Length for 5G Beam Sweeping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In 5G New Radio communication systems, the increased path loss at higher carrier frequencies necessitates beamforming with a large antenna array, leading to narrow beam coverage and a high number of beam sweeps, which increases the false alarm rate during time-index decoding due to the inefficiency of current CRC methods.
Innovation Solution
Adaptive selection of CRC length based on the number of beam sweeps, antenna configuration, and operating carrier frequency, using a CRC polynomial to generate CRC bits and concatenate them with time-dependent or time-independent information bits for efficient decoding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If beamforming with large antenna array is used to compensate for path loss at high frequencies, then signal coverage is improved, but beam coverage becomes narrow and number of beam sweeps increases
Solution Approach 1:
The patent applies dynamics by making the CRC length adaptive rather than fixed. The CRC length dynamically adjusts based on the detected number of beam sweeps, allowing the system to optimize error detection capability according to actual transmission conditions. This resolves the contradiction by enabling the receiver to handle variable beam sweep scenarios efficiently.
Solution Approach 2:
The patent changes the parameter of CRC length based on system conditions. By detecting the number of beam sweeps and selecting an appropriate CRC length from a set of possible lengths, the system adapts the error detection mechanism to match the complexity of the beam sweeping scenario, thereby managing the trade-off between coverage reliability and decoding complexity.
2Device complexity
If fixed CRC length is used for time-index decoding, then decoding complexity is reduced, but false alarm rate increases with high number of beam sweeps
Solution Approach 1:
The patent makes the CRC length dynamic by detecting the number of beam sweeps and selecting the appropriate CRC length accordingly. This dynamic adjustment allows the system to maintain low decoding complexity for scenarios with fewer beam sweeps while increasing false alarm detection capability when the number of beam sweeps is high, thus resolving the contradiction between complexity and reliability.
Solution Approach 2:
The system changes the CRC length parameter based on the detected number of beam sweeps. By selecting from a set of predefined CRC lengths, the system optimizes the balance between decoding complexity and false alarm rate, allowing flexible adaptation to different transmission scenarios without requiring complex real-time calculations.
3Reliability
If CRC length is increased to reduce false alarm rate, then reliability improves, but latency and power consumption increase
Solution Approach 1:
The patent applies dynamics by adjusting the CRC length based on the actual number of beam sweeps detected. Instead of always using a long CRC to minimize false alarms, the system selects the appropriate CRC length from a set of options, thereby reducing unnecessary latency and power consumption when fewer beam sweeps are used, while maintaining high reliability when needed.
Solution Approach 2:
The system changes the CRC length parameter adaptively based on system conditions. By selecting from a set of predefined CRC lengths rather than always using the maximum length, the system optimizes the trade-off between false alarm rate and decoding latency, reducing power consumption and processing time when high CRC length is not necessary.
Data Source
AI summary
According to some embodiments, a method for use in a wireless transmitter of adaptive cyclic redundancy check (CRC) length selection comprises: obtaining a system parameter related to a number of beam sweeps used by the wireless transmitter for transmitting a wireless signal; selecting a CRC length based on the obtained system parameter; selecting a CRC polynomial of the selected length; generating CRC bits from time-dependent or time-independent information bits using the CRC polynomial; concatenating the generated CRC bits with the time-dependent or time-independent information bits; encoding the concatenated bits; and transmitting the encoded bits to a wireless receiver. The system parameter may comprise: a carrier frequency; a number of transmit antenna elements; a number of receive antenna elements; a transmitter antenna azimuth configuration; a transmitter antenna elevation configuration; an antenna polarization type; a beam scanning algorithm; and a cell type.