Shared Bluetooth PLL and DDFS for Simultaneous NFC and FM

Solution Overview

Problem

Conventional mobile terminals face challenges in integrating Bluetooth, near field communication (NFC), and FM transmission and reception functions due to different frequency spectrums requiring separate oscillator circuits, which consume extra power and increase device size and complexity, leading to interference issues.

Innovation Solution

A system and method that integrate Bluetooth, NFC, and FM transmission and reception functions onto a single chip, using a direct digital frequency synthesizer (DDFS) clocked by a signal generated via a Bluetooth LOGEN or PLL, enabling simultaneous operation by adjusting control word inputs for frequency compensation and time division duplexing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If separate oscillator circuits are used for each wireless communication protocol (Bluetooth, NFC, FM), then each protocol can operate independently with stable frequency, but power consumption increases and device size and complexity increase

Engineering Contradiction:

Improvefrequency stabilityVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent merges multiple oscillator circuits into a single shared oscillator that serves Bluetooth, NFC, and FM communication protocols simultaneously. This consolidation reduces the total number of oscillators needed, thereby lowering power consumption while maintaining frequency stability through digital frequency synthesis techniques.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent implements a universal oscillator system that can generate frequencies for multiple different wireless communication protocols (Bluetooth, NFC, FM) using a single hardware component. This multi-functional approach allows one oscillator to replace what would traditionally require separate dedicated oscillators for each protocol.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Reliability

If separate oscillator circuits are used for each wireless communication protocol (Bluetooth, NFC, FM), then each protocol can operate independently with stable frequency, but device size and complexity increase

Engineering Contradiction:

Improvefrequency stabilityVSAvoidnumber of oscillator circuits

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges multiple oscillator circuits into a single shared oscillator that serves Bluetooth, NFC, and FM communication protocols simultaneously. This consolidation reduces the total number of oscillators needed, thereby lowering power consumption while maintaining frequency stability through digital frequency synthesis techniques.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent introduces a direct digital frequency synthesizer (DDFS) as an intermediary component that takes the output from a single shared oscillator and generates the appropriate frequency signals for different wireless communication protocols. This mediator enables one oscillator to support multiple protocols without direct interference between them.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Adaptability or versatility

If multiple oscillator circuits are integrated into a single mobile terminal, then multiple wireless communication protocols can be supported, but interfering signals are picked up between clock signals from different oscillators

Engineering Contradiction:

Improveprotocol compatibilityVSAvoidsignal interference

Core Design Contradiction:

Adaptability or versatilityVSObject-generated harmful factors

Solution Approach 1:

The patent introduces a direct digital frequency synthesizer (DDFS) as an intermediary component that takes the output from a single shared oscillator and generates the appropriate frequency signals for different wireless communication protocols. This mediator enables one oscillator to support multiple protocols without direct interference between them.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces traditional analog oscillator circuits with a direct digital frequency synthesizer approach, where digital logic and algorithms are used to generate frequency signals. This substitution of digital for analog mechanisms reduces signal interference and improves spectral purity.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentUS7937107B2Method and system for Bluetooth, near field communication and simultaneous FM transmission and reception functions

Publication Date: 2011.05.03 NXP USA INC

AI summary

Methods and systems for wireless communication are disclosed and may comprise generating a first signal to enable transmission and/or reception of Bluetooth signals, and clocking direct digital frequency synthesizers (DDFSs) via the first signal to enable simultaneous transmission and reception of FM and NFC signals. The first signal may be generated via a Bluetooth LOGEN or PLL, and may comprise in-phase and quadrature components. The frequency of the first signal may be within the range of 2.4 GHz to 2.483 GHz, or mixed to result in a frequency within the same range. Control word inputs may be generated to control the DDFSs, and may be adjusted to compensate for changes in frequency of the first signal. Simultaneous NFC transmission and reception may be simulated by switching the control word inputs between a plurality of values in successive time intervals to perform time division duplexing, and may occur at different frequencies.