Slotted Directional RTS Reception for Wireless Medium Reuse
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, especially those compliant with the IEEE 802.11 ad standard, network congestion leads to interference when multiple devices transmit Request to Send (RTS) messages simultaneously, preventing intended recipients from transmitting a clear to send (CTS) message and thus hindering subsequent data transmission.
Innovation Solution
Implementing slotted and directional transmission and reception of RTS messages, where receiving devices perform beam training with neighboring devices to determine optimal spatial directions and allocate specific time slots for RTS messages, reducing interference and enhancing medium reuse.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple devices transmit RTS messages simultaneously in a congested network, then network utilization increases, but interference increases and prevents intended recipients from receiving messages
Solution Approach 1:
The patent segments the transmission medium by introducing directional beams that divide the omnidirectional space into specific spatial sectors. Each beam serves a particular directional sector, allowing multiple RTS messages to be transmitted simultaneously in different directions without interfering with each other, thus resolving the contradiction between network utilization and interference
Solution Approach 2:
The patent transitions from omnidirectional (360-degree) transmission to directional transmission by adding spatial dimension control through beamforming. This dimensional change allows the system to distinguish between signals from different directions, enabling simultaneous transmissions in different spatial dimensions without mutual interference
2Adaptability or versatility
If receiving devices remain in omni-directional mode, then they can receive signals from any direction, but interference from other devices prevents successful reception
Solution Approach 1:
The patent applies local quality by making the reception characteristic direction-specific rather than uniformly omnidirectional. Each receiving device configures its beam to have high gain in the specific direction of the intended transmitter while maintaining lower gain in other directions, thus selectively receiving signals from the intended source while rejecting interference from other directions
3Ease of operation
If RTS messages are transmitted without time slot allocation, then transmission simplicity is maintained, but network congestion causes collisions and failed receptions
Solution Approach 1:
The patent applies preliminary action by performing beam training and spatial direction determination before actual RTS message transmission. Devices pre-establish beam configurations and time slot allocations based on spatial relationships, so that when RTS messages are transmitted, the directional beams and time slots are already optimized, ensuring reliable reception without complex real-time coordination
Data Source
Figure 1
Figure 2A~2D
Figure 3
AI summary
A receiving device may remain in omni-directional mode while receiving RTS messages from transmitting devices. Multiple devices may transmit RTS messages at the same time, causing interference and preventing intended recipients of the RTS messages from transmitting a CTS message. To increase medium reuse, RTS may be transmitted and received in a slotted and directional manner. A receiving device may select a sweeping pattern for receiving transmission from neighboring devices. The receiving device may also determine one or more time slots allocated to each of the neighboring devices for receiving transmissions from the neighboring devices. The receiving device may transmit an indication of the sweeping pattern and the time slots to one or more of the neighboring devices. Subsequently, during one of the indicated time slots, the receiving device may perform a beam sweep to receive one or more RTS messages from one of the neighboring devices.