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Kommunikatsiooniteenuste arendusIRT0080

Loeng 11/2008

Avo Otstelekommunikatsiooni õppetool,

TTÜ raadio- ja sidetehnika inst.avo.ots@ttu.ee

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Many Radios ...Limited Spectrum

Near Field Communication

60GHzUWB BluetoothWiMAX Wi-Fi

A,B,G,N 3G TV- DVB GPS

FM

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Use Cases

• Many applications including … – Delivering multiple HD streams to several receivers– Displaying stored digital contents from media servers to display devices– Browsing contents in distributed devices through big screen TVs

Home PC

STB (Cable TV access)

DTV

Wireless AP(Internet gateway)

Digital cameraCamcorder

PMP

DVD player

Projector

Home theater(AV receiver)

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Multicast

– Content server multicasts multimedia streams to many authenticated users.

– Regardless of how many users receive the streams, a single WLAN channel is expected to be used.

– Content server can be STB, PC, AP, or even any portable devices.

PMPLaptop PC

AP

STB (Cable TV access)

Home PC

PMP

PMP

Laptop PC

PMP

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One TS contains audio, video, data

TS Header (4 bytes) has an adaptation field control. This is used among other things to identify the presence of PCR (Program Clock Reference) following the header.

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CodecBit rate (Mbps)

Loss period(# of IP packets)

Acceptable average PER

(Packet Loss w/zero retries)

MPEG-2 (HDTV)

15.0 24 <= 1.17 E-06

17 27 <= 1.16 E-06

18.1 29 <= 1.17 E-06

MPEG-4 (HDTV)

8 14 <= 1.28 E-06

10 17 <= 1.24 E-06

12 20 <= 1.22 E-06

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Max duration of an error event <= 16 ms; 1 error event per 4 hoursMax video/audio delay < 200/50 ms; max jitter < 50 ms

Parameters*

* From TR-126 www.dslforum.org

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Multi-Radio Concurrent Usages

WiMAX CoverageWiMAX Coverage

Wi-Fi CoverageWi-Fi Coverage

Bluetooth CoverageBluetooth Coverage

Bluetooth CoverageBluetooth Coverage

in home / officein home / office

on the road on the road

Seamless HandoverSeamless HandoverSeamless HandoverSeamless Handover

Wireless GatewayWireless Gateway

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Wi-Fi / WiMAX /BluetoothWi-Fi (802.11g) WiMAX

(802.16e)Bluetooth

Range 100m 1000m 3m

Bandwidth 20MHz 10MHz 1MHz

Media Access CSMA OFDMA TDMA

Peek Data Rate 54Mbps 64Mbps (2x2) 3Mbps

QoS Support Low High Medium

Spectrum Unlicensed Licensed / Unlicensed

Unlicensed

TX Power 20dBm 24dBm 0dBmWireless technologies have different sweet spots of operation in terms of coverage, QoS, power, throughput, etc.

Wireless technologies have different sweet spots of operation in terms of coverage, QoS, power, throughput, etc.

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Inter-Radio Interference

GPS

UWB

BT

CDMA 1800

GSM 800

Wi-Fi

WiMax

UWBBTCDMA180

0GSM 800Wi-FiWiMax

Isolation Requirements

Severe Moderate Cautious No-problem>55db 40-55db 25-40db <25db

MotivationMotivation

Interferer Interferer Victim Victim

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Linkhttp://www.compression.ru/video/quality_measure/index_en.html