Frequency Selective Scheduling via Uplink Data Channel Estimation
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Solution Overview
Problem
Frequency selective scheduling in wireless communication networks is hindered by the need for explicit channel sounding, which increases overhead and is inefficient, especially in scenarios with fast-changing channels or a large number of wireless devices.
Innovation Solution
A method where a wireless network node transmits a first packet over the entire available bandwidth to identify addressed wireless devices and downlink sub-carriers, and receives a second packet on uplink sub-carriers to determine channel quality indications without explicit sounding, allowing for efficient frequency selective scheduling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If explicit channel sounding is used to obtain channel knowledge for frequency selective scheduling, then scheduling performance is improved, but overhead increases and time is lost
Solution Approach 1:
The system uses the uplink data packets that wireless devices must transmit anyway to carry channel sounding information. The channel knowledge is obtained from the devices' own transmissions rather than requiring separate dedicated sounding sequences, thus the system serves itself and eliminates the need for additional overhead.
Solution Approach 2:
The uplink data packets serve dual purposes: they carry both the actual data information and the channel sounding information simultaneously. This multi-functionality allows the system to obtain channel knowledge without requiring separate dedicated sounding resources, thereby reducing overhead and time loss.
2Measurement precision
If explicit channel sounding is performed to estimate channels for multiple wireless devices, then frequency selective scheduling accuracy is improved, but overhead becomes prohibitive
Solution Approach 1:
The uplink data packets serve dual purposes: they carry both the actual data information and the channel sounding information simultaneously. This multi-functionality allows the system to obtain channel knowledge without requiring separate dedicated sounding resources, thereby reducing overhead and time loss.
Solution Approach 2:
The patent extracts the channel sounding information from the uplink data packets that are already being transmitted. By taking out the channel knowledge from the existing data transmissions rather than requiring separate sounding sequences, the system reduces overhead while maintaining measurement precision.
3Measurement precision
If channel knowledge is obtained through dedicated sounding sequences, then channel estimation is accurate, but the time required reduces the gain during actual data transmission
Solution Approach 1:
The system maintains continuous useful action by using the uplink data transmissions for both data communication and channel sounding simultaneously. There is no interruption or separate phase for channel measurement, as the channel knowledge is obtained continuously from the ongoing data transmissions, thereby maintaining high data transmission efficiency.
Solution Approach 2:
The patent merges the channel sounding function with the uplink data transmission function. By combining these two functions into a single transmission process, the system eliminates the need for separate sounding sequences and maintains continuous productive activity, thereby improving overall data transmission efficiency.
Data Source
AI summary
There is provided mechanisms for frequency selective scheduling of wireless devices in a communication network. A method is performed by a wireless network node. The method comprises transmitting a first packet to at least one wireless device over the entire available bandwidth of the communication network, wherein the first packet comprises information identifying which wireless devices are addressed by the packet, and which downlink sub-carriers are used for data transmission to the addressed wireless devices. The method comprises receiving a second packet on uplink sub-carriers allocated to at least the addressed wireless devices and therefrom determining channel quality indications for the uplink sub-carriers. The uplink sub-carriers are allocated to enable the channel quality indications to be determined over the entire bandwidth for at least each one of the addressed wireless devices.