Electrical & Computer Engineering

Wireless Music Sharing

Team Ganz:Mike O’Malley™

Ben LaPointeErik Christensen

Nhat Khai Nguyen

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Scenario

John and Matt are listening to music in ECE 232 John wants to listen to Matt’s music Matt sets his “Team Ganz” player to transmit John sets his “Team Ganz” player to receive John now has Matt’s music streaming wirelessly

to his headphones Jill wakes up and sees John listening to Matt’s

music She sets her “Team Ganz” player to receive John and Jill are both listening to Matt’s music

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Goals

Allow music to be shared wirelessly between portable music players

Broaden users’ musical exposure

Store information on music listened to for later purchase

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Big picture: User level

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Proposed device functionality

Transmit Mode• Listen to your own music• Wirelessly send current music selection to other users• Provide data such as song title, artist, and player ID

Receive Mode• Wirelessly receive music from transmitter• Displays data such as song title and artist to user• Allow user to rate the music selection• Able to select which transmitter to receive from

Sync Mode• Sync song information and ratings to PC• Store MP3s on music player• Charge battery

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Inter-device Diagram

Bluetooth Decoder Head PhonesCodecBluetoothCodecAudio Source

Transmitter Receiver

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Possible Audio Source Models

Line in audio source (In-line Encoder)

Bluetooth audio source (Repeater)

Standalone

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Line in audio source (In-line Encoder)

Features• Used to support legacy digital music players• Must encode stereo audio• Song information provided through manufacturer

specific connection• Insert inline between player and headphones

Pros• Compatible with any analog audio source• Users can keep existing player

Cons• Song information may not be available• Song information through vendor specific cable

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Bluetooth audio source (Repeater)

Features• Support Bluetooth players and accessories such as

naviPlay for the iPod• Bluetooth must be able to receive and transmit at the

same time

Pros• Transmitting requires no codec conversions• Compatible with other Bluetooth transmitters

Cons• Repeater will have to use a Bluetooth 2.x Enhanced

Data Rate (EDR) chipset – 3Mbps allows multiple stereo audio links

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Standalone Audio Source

Features• Built-in Flash or Disk storage• Needs MP3 Decoder• Song info from ID3 tags

Pros• Time-invariant audio source• Complete control over the audio path• ID3 tags provide easy song information

Cons• Users must switch to our device and discard previous

player• Added expense of MP3 decoder

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Block Diagram

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Wireless Design Goals

Near CD quality sound Range between 10 and 100 meter

• Trade off with power consumption

Multiple Transmitters in the same area Broadcast from one transmitter to several

receivers Transmit song and user data Standardized for compatibility

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Wireless Options

FM with Radio Data System (RDS)• Broadcasts well• Find empty frequencies• Small amount of data in RDS

WiFi 802.11• 100m range (power hungry)• Needs to use multicast for broadcasting• Needs to form Ad-hoc networks and discover devices

Zigbee – only meant for slow data rates WiMedia – chipsets do not have advanced features Bluetooth

• <10m, 10m, or 100m device classes• Point to Multipoint available on some chipsets• Chips made to transmit stereo audio to headsets• Can only broadcast to 7 other devices• Generic Media Control Profile for song and other information

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One Proposed Solution

Broadcom BCM2037• Bluetooth 2.0 with Enhanced Data Rate (EDR)• 3 Mbps• Multiple stereo links• Low power• Integrated Radio

STA027• SBC codec• Stereo encoding and decoding

STA013• MP3 decoder

TI stereo audio codec

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Currently Selected Parts Block Diagram

StorageFlash / Disk

Battery

USBPC Connetion

Encoder Decoder

Bluetooth

LCD

Buttons

CPU

System on a Chip

Head Phones

To PC

Line In

Digital Info

In Line Encoder Model

Standalone Model

TI Audio Codec

Broadcom Bluetooth Soc

TBD

Flash and MP3 Codec (STA013)

TI Power Management

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Current Status

TI samples in route

ST Microelectronics samples in route

Emails out to Bluetooth chips manufactures and distributors

Will make calls next week to lock in Bluetooth SoC

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Design Dilemma Matrix

Manufacturer Model BT 1.xBT 2.x EDR A2DP

AVRCP SBC MP3 Flash USB I2S I2C

Broadcom BCM2037 x x x x x x x x x

CSRBluecore3 -

Multimedia x x x x x x x x

Bluecore4 x x x x x

Bluecore5 -Multimedia x x x x x x x x x

RF Micro SiW4000 x x x x x x x x

GCT Semiconductors GDM5104 x x x x x x x x

TI BRF6300 x x x x x

Xemics ZE1401 x x x x x x x x

ST Microelectronics STA013 x x x

STA027 x x x

Portal Player PP5024 x x x x x

Atmel AT83SND2CMP3 x x x x x

SigmaTel STMP35xx x x x x x

Cirrus Logic EP7312 x x x x x

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MPR Specifications

Test I2S and I2C buses

Test each chip to learn how to integrate it

Sample communications over Bluetooth

Hardware layout