Wireless PDR

8/3/2019 Wireless PDR

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ECEN 4610 Spring 2006Hands-Free Low-Profile Wireless Radio

Preliminary Design Review Handmade by Robots

Team members

Derek LindbergSean McDevitt

Nick Ciocco

Eric Hoffman

Chris Browne

Team: Wireless Nothing

Preliminary Design Review


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Two-way wireless communication betweento separate motorcycles.

One-way wireless CD quality audio

streaming from a portable devices audio jack.

Adjustable volume, microphone gain, andchannel selection.

Restricted access to broadcasted audio. Modular implementation of a wireless

communication and audio listening device

What is this Device?


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High Level Concept

Short range RF

Short range RF

Long Range RF


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DAC CodecADC Codec

MicrocontrollerMicrophone Headphones

Transceiver

Functional Block Diagram - Headset

I2

C

I2

S I2S

I2C Bus


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ADC/DAC OR Transceiver

TransceiverSingle Chip Wireless Transceiver (nRF24Z1)

2.4 GHz operating frequency Low cost Low power High-fidelity sound (16-bit)

Channel selection Integrated control channel

1Mbit/s 4Mbit/s Data Rate I2S or S/PDIF Audio Input (16bit) SPI or I 2C Integrated Frequency Hopping Scheme

I2S

I2C

Microcontroller

ReceivingTransceiver

Transceiver


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Size ~ 23cm x 1.5mm2.4 GHz Printed Monopole

Size ~ 12mm x 20mm

2.4 GHz Printed Whip Monopole

2.4 GHz Chip Antennas Size ~ Tiny < 1cm 2 Reduced gain from reduced size

Antenna Considerations


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DAC CodecADC Codec


Transceiver

Functional Block Diagram Headset, DAC/ADC

I2

C

I2

S I2S

I2C Bus


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Microphone

Microcontroller

Headphones MP3 Player

DAC / ADC

Single Chip DAC/ADC I 2S Codec Convert between analog and I 2S Low power low cost High quality 16 bit sound DAC and ADC in single chip for simplicity Integrated gain control, volume control and

speaker drivers if possible I2S communication to Transceiver I2C control from Microcontroller

I2S

Transceiver

I2C

Analog

DAC/ADC


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DAC CodecADC Codec


Transceiver

Functional Block Diagram - uC

I2

C

I2SI2S

I2C Bus


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Transceiver(s)

Microcontroller

Primary Functions Timing Control power consumption User feedback (tones, battery level) Process user input (buttons)

Microcontroller (MSP430F156) Features 24kB Flash, 1024B RAM Very-low power

330uA active 1.1uA standby mode

12bit DAC I2C and SPI interfaces in hardware 48 IO pins

Overkill, but we will never have to worryabout exceeding code space or havingtoo few IO pins during dev.

I2C

ADC/DAC

Microcontroller


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State Diagram Headset

InitBase Station

Search Idle

Rx

Tx

Always Base Station Found

Wait Wait


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High Level Concept

Short range RF

Short range RF

Long Range RF


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State Diagram Base Station

InitHeadsetSearch Idle

LocalAudio

RemoteTx/Rx

V oi c e T i m

e o u t

V o

i c e

D e t e c

t e d

Always Headset Found

Wait Wait


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High Level Concept

Short range RF

Short range RF

Long Range RF


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Functional Block Diagram - Media Device

ADC Codec

MicrocontrollerMedia Device

Transceiver

AnalogI2C

I2S

I2C Bus

Transmits streaming wireless audio from aportable device such as an mp3 player

Audio is played back in the helmet Has a lower priority than voice comm Same PCB as Helmet

(headphone portion left unpopulated) Simplifies Design Single circuit to debug


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State Diagram Media Device

InitBase Station

Search IdleRemote

Tx

Always

Audio Timeout

Base Station Found

Wait Wait

Audio LevelsPresent


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Highly Modular Design

uC

AudioCodec

AudioCodec

uC

Tx/Rx

Tx/RxTx/Rx

Tx/Rx

uC

Tx/Rx

AudioCodec

Base Station Headphone/MicWireless AudioTransmitter

Each component is composed of several re-useable modules We only need to do low-level design and testing once


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Division of Labor

Group Responsibilities Documentation, system development, integration, system testing, and

documentation

Team members Responsibility

Derek Lindberg Hardware layout and assembly,firmware programming

Sean McDevitt Antenna and Transceiver design

Nick Ciocco Transceiver design and PCB layoutoverview

Eric Hoffman Hardware layout and assembly,firmware programming

Chris Browne Assembly firmware programming,hardware integration

S i 2006


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Project Timeline

S i 2006


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Risks and Contingencies

Risks Unfamiliar Interfaces and Devices

I2C/S, Transceiver, Codec Difficulty controlling codec/transceiver

w/ uC Limited transmit range / Problems w/

interfering devices Lead time on components / Availability

problems Difficulty getting RF link working

(RF protocol)

Compliance with FCC regulations

Prevention Help from TAs, Manufacturers, Dev

Boards Nordic, Texas Instruments

May be short range for Expo

Ordering samples far ahead of time

Use Nordic dev board

Will ignore them

S i 2006


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P li i D i R i H d d b R b t

Questions ?

Wireless PDR

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