PN Quadrature Covering Masks for xHRPD Access Channel Interference
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for access channel procedures in xHRPD systems are susceptible to inter-cell interference, making it difficult to differentiate between distinct access channels, and do not adequately address issues of intra-cell interference and channel collisions in narrowband access channels.
Innovation Solution
The method involves generating enhanced Pseudo-Noise (PN) quadrature covering masks using specific bits of the assigned channel number and performing exclusive OR operations on certain bits of the access long code masks MIACMAC and MQACMAC to create MI and MQ masks for the access channel, which are used for In-phase and Quadrature-phase modulation, respectively, to improve channel differentiation and robustness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional access channel masks are used in xHRPD systems, then device complexity is reduced, but inter-cell interference increases and channel differentiation becomes difficult
Solution Approach 1:
The patent modifies the access channel mask generation by changing parameters: extending channel number bits from 4 to 6 or 8 bits, and applying exclusive OR operations between extended channel bits and long code mask bits. This parameter change enhances channel differentiation capability while maintaining manageable device complexity through systematic processing.
Solution Approach 2:
The mask generation process is segmented into distinct steps: (1) obtaining long code masks, (2) extending channel number bits, (3) performing exclusive OR operations on specific bits, and (4) generating final access channel masks. This segmentation makes the complex process more manageable and implementable.
2Use of energy by moving object
If narrowband channels are used in hybrid satellite/terrestrial networks, then power consumption is reduced, but intra-cell interference increases and channel distinction becomes difficult
Solution Approach 1:
The patent extends channel number bits from 4 to 6 or 8 bits and applies exclusive OR operations with long code masks, creating more distinctive mask patterns for narrowband channels. This enhances channel distinction capability while maintaining the power efficiency benefits of narrowband operation.
3Speed
If access channel masks are generated using only 4-bit channel numbers, then processing speed is maintained, but interference resistance decreases
Solution Approach 1:
The patent performs preliminary anti-action by extending channel number bits and applying exclusive OR operations before mask generation. This preemptive enhancement of mask distinctiveness prevents interference issues before they occur, while the systematic processing maintains acceptable generation speed.
Data Source
AI summary
Disclosed is a method of performing Pseudo-random-Noise (PN) quadrature covering for transmitting data via an access channel. Such method is achieved by receiving a 42-bit access long code mask MIACMAC and a 42-bit access long code mask MQACMAC from an upper layer; generating an MI mask and an MQ mask for PN quadrature covering by using certain bits of an assigned channel number for the access channel and by performing exclusive OR operations on certain bits of the received access long code mask MIACMAC and performing exclusive OR operations on certain bits of the received access long code mask MQACMAC; and transmitting signals via the access channel based on the generated 12-bit MI mask and the generated 12-bit MQ mask.