Time Hopping for Wireless Peer Discovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication networks, terminals face challenges in detecting other terminals due to half-duplex operation limitations and desensing issues, where strong signals mask weak signals, making peer discovery inefficient.
Innovation Solution
The use of time hopping and time-frequency hopping techniques allows terminals to select different slots or resource units in each frame, enabling efficient peer discovery by shifting transmission slots or resource units based on specific functions, such as pseudo-random number generators or Latin squares, to avoid collisions and desensing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If terminals use fixed slots for transmission in peer-to-peer communication, then the communication structure is simple, but detection efficiency is low due to half-duplex limitations and desensing issues
Solution Approach 1:
The patent applies dynamics by making the transmission slots dynamic through time-hopping sequences. Instead of fixed slots, terminals use variable slot assignments that change over time according to hopping patterns. This allows terminals to detect each other more efficiently by trying multiple slot configurations, resolving the contradiction between detection efficiency and structural simplicity.
Solution Approach 2:
The patent introduces time-hopping sequences that add a temporal dimension to slot allocation. By incorporating time-varying hopping patterns across multiple frames, the system transforms a static slot structure into a multi-dimensional time-slot structure, enabling efficient peer discovery while managing complexity through structured temporal variation.
2Object-affected harmful factors
If terminals transmit in the same slot, then resource utilization is efficient, but desensing occurs where strong signals mask weak signals
Solution Approach 1:
The patent segments the transmission resources by assigning different time-hopping sequences to different terminals. This segmentation distributes transmissions across multiple slots and frames, preventing simultaneous transmissions that cause desensing while maintaining efficient resource utilization through structured time-division multiplexing.
Solution Approach 2:
The patent employs periodic time-hopping sequences where terminals transmit in periodic intervals according to their assigned hopping patterns. This periodic action ensures that strong and weak signals are separated in time, eliminating signal masking while maintaining regular transmission rhythms for efficient resource usage.
3Productivity
If terminals use time hopping to avoid collisions, then peer discovery efficiency improves, but the complexity of slot selection increases
Solution Approach 1:
The patent uses parameter changes by varying time-hopping sequences based on terminal identities and frame numbers. This systematic parameter variation enables efficient peer discovery through structured slot selection, where the complexity is managed through predefined hopping patterns rather than arbitrary slot selections.
Solution Approach 2:
The patent implements self-service through autonomous time-hopping sequence generation at each terminal. Each terminal independently generates its hopping pattern based on its identity and the frame counter, eliminating the need for centralized slot assignment and reducing overall system complexity while maintaining fast detection capability.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
Techniques for transmitting signals using time hopping or time and frequency hopping are described. In one design, a terminal selects different slots to use for transmission in multiple frames with time hopping. Each frame includes multiple slots, and each slot covers a particular time duration. The selected slots are at different time locations in the multiple frames. In another design, a terminal selects different resource units to use for transmission in multiple frames with time and frequency hopping. The selected resource units are at different time and frequency locations in the multiple frames. For both designs, the terminal sends a signal (e.g., a peer discovery signal) in the selected slots or resource units in the multiple frames. The terminal may detect for signals (e.g., peer discovery signals) from other terminals in slots not used for transmission by the terminal.