LTE Uplink Narrowband Subcarrier Assignment for Low Capability Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Low capability wireless devices in LTE networks require significant processing resources for uplink communication, which is incompatible with machine-to-machine (M2M) devices that typically send small amounts of data, leading to network overload and increased costs, as existing solutions only reduce the frequency band to 1.4 MHz without easing processing requirements.
Innovation Solution
Implementing a method where the base node assigns a subcarrier to the wireless device for data transmission using a narrowband modulation scheme, such as continuous wave (CW) or Gaussian Minimum Shift Keying (GMSK), which reduces processing power and allows data transmission on a single subcarrier, embedded within the SC-FDMA structure, and indicating support for this modulation scheme to the device.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If LTE standard is implemented to support high bandwidth and reduced latency, then network capacity and service quality are improved, but processing resources and hardware requirements for wireless devices increase significantly
Solution Approach 1:
The patent segments the uplink transmission resources by introducing a narrowband transmission mode that occupies only a portion of the system bandwidth rather than the full bandwidth. This allows low capability devices to transmit data using a segmented, reduced portion of the frequency spectrum, thereby reducing processing requirements while maintaining network capacity for other devices
Solution Approach 2:
The patent applies local quality by providing different transmission modes for different device types. Low capability devices use the narrowband transmission mode with reduced processing requirements, while other devices continue to use the full LTE transmission mode. This localized adaptation allows the network to support diverse device capabilities without compromising overall network performance
2Ease of manufacture
If low capability wireless devices are deployed to reduce costs, then device affordability is improved, but network overhead and signaling load increase
Solution Approach 1:
The patent extracts the essential data transmission function from the full LTE protocol stack by implementing a simplified narrowband transmission mode. This extracted mode retains only the necessary components for data transmission while removing complex signaling and processing elements, thereby reducing device cost and network overhead simultaneously
3Device complexity
If frequency band is reduced to 1.4 MHz for low capability devices, then processing resources are reduced, but transmission capacity and data rate are limited
Solution Approach 1:
The patent introduces dynamic resource allocation where low capability devices can use the narrowband transmission mode when data rates are not critical, but the system can dynamically allocate additional resources or switch modes when higher data rates are needed. This dynamic adaptation allows the same device to operate efficiently across different data rate requirements without permanently limiting capacity
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention relates to a method for data transmission from a wireless device to a base node, the base node is part of a cellular network and is configured to support frequency division multiple access method, the bandwidth receivable by the base node comprising a plurality of subcarriers, the wireless device is camping on the base node, the method comprises the steps of: - for the base node, assigning to the wireless device a subcarrier of the plurality of subcarriers, - transmitting data from the wireless device to the base node for the period of at least one data service session using only the assigned subcarrier, whereby using for said data transmission a first modulation scheme on the assigned subcarrier different from the modulation scheme used for more than one of the plurality of the subcarriers by at least one second wireless device camping on said base node.