Variable-Antenna Base Station for Shared MIMO-OFDM Reception

Solution Overview

Problem

In radio base stations, the increasing number of antennas for MIMO-OFDM signal reception leads to higher costs and power consumption due to the need for multiple RF units and ADC units.

Innovation Solution

A radio base station with a characteristic variable antenna that periodically switches antenna characteristics in synchronization with the reception sampling period, sharing an RF unit and ADC unit to process and divide signals, allowing for efficient MIMO-OFDM demodulation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the number of antennas is increased for MIMO-OFDM signal reception, then the transmission speed and efficiency are improved, but the costs and power consumption increase due to the need for multiple RF units and ADC units

Engineering Contradiction:

Improvetransmission speedVSAvoidpower consumption

Core Design Contradiction:

ProductivityVSUse of energy by stationary object

Solution Approach 1:

The patent merges the functions of multiple RF units and ADC units into a single shared unit by implementing time-division multiplexing. The antenna switching unit alternates connection between multiple antennas and the single RF/ADC unit at predetermined timing, allowing the same hardware to process signals from multiple antennas sequentially, thereby reducing the total number of RF and ADC units needed while maintaining MIMO capability

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent introduces dynamic switching of antenna connections to the RF unit and ADC unit. The antenna switching unit dynamically changes which antenna is connected to the shared RF/ADC unit based on predetermined timing, enabling the system to handle multiple antenna signals with a single hardware chain through time-varying configuration

Inventive Principle:

Principle #15Dynamics

2Productivity

If the number of antennas is increased for MIMO-OFDM signal reception, then the transmission efficiency is improved, but the costs increase due to the need for multiple RF units and ADC units

Engineering Contradiction:

Improvetransmission efficiencyVSAvoidcost

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent merges the functions of multiple RF units and ADC units into a single shared unit by implementing time-division multiplexing. The antenna switching unit alternates connection between multiple antennas and the single RF/ADC unit at predetermined timing, allowing the same hardware to process signals from multiple antennas sequentially, thereby reducing the total number of RF and ADC units needed while maintaining MIMO capability

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent makes a single RF unit and ADC unit universal by enabling it to serve multiple antennas through time-division multiplexing. The shared RF/ADC unit can process signals from any of the multiple antennas by switching connections at predetermined timing, making the hardware multi-functional and reducing the need for dedicated units for each antenna

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Reliability

If multiple RF units and ADC units are installed for each antenna, then the signal processing capability is improved, but the power consumption increases

Engineering Contradiction:

Improvesignal processing capabilityVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by stationary object

Solution Approach 1:

The patent merges the functions of multiple RF units and ADC units into a single shared unit by implementing time-division multiplexing. The antenna switching unit alternates connection between multiple antennas and the single RF/ADC unit at predetermined timing, allowing the same hardware to process signals from multiple antennas sequentially, thereby reducing the total number of RF and ADC units needed while maintaining MIMO capability

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent implements periodic switching of antenna connections to the shared RF unit and ADC unit. The antenna switching unit connects different antennas to the shared hardware at regular intervals according to predetermined timing, enabling time-division multiplexing that reduces power consumption while maintaining the ability to process multiple antenna signals

Inventive Principle:

Principle #19Periodic action

Data Source

PatentUS11804881B2Radio base station and reception method at radio base station

Publication Date: 2023.10.31 NIPPON TELEGRAPH & TELEPHONE CORP

AI summary

A characteristic variable antenna configured to be able to select or switch antenna characteristics in accordance with a predetermined periodic variable timing, an RF unit configured to perform a reception process on a signal received by the characteristic variable antenna, an ADC unit configured to sample the analog signal input from the RF unit at a sampling period corresponding to the variable timing of the antenna characteristics of the characteristic variable antenna, a signal dividing unit configured to divide the digital signal input from the ADC unit into different digital signals in accordance with the antenna characteristics and output the divided different digital signals, a MIMO-OFDM demodulation unit configured to receive inputs of the different digital signals divided by the signal dividing unit and perform a demodulation process of predetermined MIMO-OFDM, and a control unit configured to periodically select or switch the antenna characteristics of the characteristic variable antenna in accordance with the sampling period of the ADC unit are included.