Cypress CY62167EV18 Uživatelský manuál stáhnout pdf (Strana 18)

US

8,121,078

B2

15

the

high-bandwidth

radio

104

and

the

low-bandwidth

radio

106

can

be

in

the

same

transceiver

block.

Additionally,

errors

in

the

bit

stream

of

the

beacon

during

transmission

can

be

corrected

by

using

forward

error

correc

tion

(FEC)

techniques,

such

as

hamming

codes.

Details

of

the

forward

error

correction

and

its

associated

timing

and

phas

ing

techniques

will

be

described

below.

The

bit

stream

can

serve

as

a

“wake-up”

function,

allowing

the

base

station

160

to

activate

the

correct

wireless

camera

to

wake-up and

per

form

certain

tasks

during times

when many

components

of

the

wireless

camera

may

be

in

the

shut

down

mode.

In

one

implementation,

this

low-bandwidth

radio

106 can

be

achieved

using

“multi-standard”

radio

design,

which

may

share

portions

or

components

used

in

the

bulk

radio

104.

The

sharing

of

“multi-standar

”

components

can

lead

to

lower

cost

or

power

from

an

overall

system

perspective.

As

noted

above,

the

wireless

camera

100

includes

an

inter

nal

battery

102,

which

can

be

a

standard

non-rechargeable

battery

or

a

battery

pack.

In

one

implementation,

a

combina

tion

of

rechargeable

and

non-rechargeable

batteries

can

be

used.

In

another

implementation,

the

rechargeable

battery

can

be

replaced

or

augmented

by

so

called

super

capacitors.

Such

capacitors

are

readily

available,

e.g.,

from

companies

like

Maxwell

Technologies

Inc.

The

sources

for

the

recharging

energy

can

include,

e.

g.,

solar

cells,

fuel

cells,

galvanic

cells,

?ow

cells,

kinetic

power

generators,

and

environmental

energy

sources.

These

energy

sources

will

be

describe

in

more

detail

below.

The

wireless

camera 100

can

make

use

of

extensive

active,

high

ef?ciency,

power

regulation

and

boaster

circuitry

to

optimize

the

use

of

the

energy

available

from

various

sources.

Some

or

all

of

electronic

processing

and

memory

elements

can

be

integrated

into

a

single

ASIC

to

reduce

cost

and

power,

creating

a

single

chip

wireless

camera.

In

addition

to

the

components

shown

in

FIG.

1,

a

Pan,

Tilt

and

Zoom

mecha

nism

and

control

can

also

be

included

for

user

control

of

the

wireless

camera

100.

FIG.

2

shows

a

battery

powered

wireless

network

camera

system

200

for

video

surveillance

applications.

In

this

example,

the

wireless

network

camera

system

200

includes

a

wireless

camera

210,

a

base

station

220,

a

wireless

link

240

connecting

the

wireless

camera 210 and

the

base

station

220,

and

a

remote

client

250.

The

system

200

can

further

include

a

network

260

connecting

the

base

station

220 and

the

remote

client

250.

The

network

260

can

be

a

LAN

or

wide

area

network

(WAN),

a

wireless

network

(e.g.,

WiFi,

WiMax,

or

cellular

networks),

or

power

over

ethemet

network

(e.g.,

based

on

the

IEEE

802.a3f

standard).

In

other

implementa

tions,

this

network

connection

can be

replaced

by

a

universal

serial

bus

(U

SB)

interconnect

directly

connected

to

a

com

puting

device.

From

the

client

250

or

network

260

perspec

tive,

the

wireless

network

camera

system

200

can

support

extensive

ethemet

protocols

including

IP,

HTTP,

HTTPS,

802.1x,

TCP,

ICMP,

UDP,

SMTP,

FTP,

DHCP,

UPnPTM,

Bon

jour,

ARP,

DNS,

DynDNS,

and

NTP.

In

particular,

the

base

station

code

can

comply

with

well

established

IP

camera

API’s

from

companies

such

as

Axis

communication’s

“VAPIX”

API

or

similar

API’s.

A

suitable

wireless

camera

in

FIG.

2

canbe

implemented

in

various

con?gurations,

including

the

wireless

camera 100

described

in

FIG.

1.

The

base

station

220

can

receive

infor

mation

(e.g.,

video

and

audio

information)

from

the

wireless

camera

210

through

the

wireless

link

240

and

process

the

received

information.

The

base

station

220

can

also

be

one

or

more

computers

performing

similar

functions

as

a

wireless

base

station

220 and

running

a

surveillance

application.

Hence,

the

computers can

function

as

the

base

station

220

and

20

25

30

35

40

45

50

55

60

65

16

the

client

250.

For

example, FIG.

3

shows

another

battery

powered

wireless

network

camera

system

300

for

remote

surveillance

applications,

where

the

surveillance

client

runs

on

the

same

system

as

the

base

station

220,

and

the

virtual

web

server

in

the

base

station

220

can

be

eliminated.

Referring

back

to

FIG.

2,

the

base

station

220

includes

a

virtual

web

server

222

for

relaying

or

transmitting

processed

information

to

a

remote

client.

The

web

server

222

can

act

as

a virtual/proxy

web

camera

server.

Further,

the

web

server

222

can

shield

the

remote

client

250

(running

a

surveillance

application)

from

the

burst

transmission

mechanism

(which

will

be

discussed

in

further

detail

below)

of

the

wireless

camera

210. In

addition,

the

web

server

222

can

act

as

a

virtual

web

server or

relay

server

for

a

number

of

wireless

cameras,

aggregating

the

video

streams

but

appearing

to

the

surveillance

remote

client

250

as

multiple

separate

virtual

IP

cameras.

The

web

server

222

can

therefore

transmit

the

cam

era

data

to

the

surveillance

client

250

using

standard

network

means

such

as

IP,

HTTP,

HTTPS,

TCP,

ICMP,

UDP,

SMTP,

FTP,

DHCP,

UPnPTM,

Bonjour,

ARP,

DNS,

DynDNS,

802.1x,

and

NTP.

As

described

above,

by

removing

the

web

server

for

a

network

camera

system

out

of

the

wireless

camera

250,

the

wireless

camera

can

achieve

ultra-low

power

consumption.

However,

unlike

the

wireless

camera

210,

the

base

station

220

requires

a

relatively

robust

external

power

supply

to

allow

for

continuous

operation

of

the

web

server

222.

This

power

sup

ply

can

have

a

battery

back-up

to

enable

operation

for

periods

of

hours

to

days

during

main

power

loss.

It

may

also

be

possible

to

power

the

base

station

220 from

a

large

battery

which

is

charged

by

a

relatively

large

solar

cell

panel.

In

another

implementation,

the

base

station

220

can

obtain

some

or

all

of

its

power

through

a

power

over

Ethernet

(POE)

methods, such

as

the

IEEE

802.3af

standard.

In

this

case

also

the

unit

may

have

battery

back-up

capabilities.

Furthermore,

the

base

station

220

can

be

a self-contained

unit

with

no

keyboard

or

monitor

to

enable

a

small

form

factor.

For

example,

the

base

station

220

can

have

a

form

factor

similar

to

that

of

a

“wall

wart,”

which

is

a

small

power

supply

brick

with

integral

male

plug,

designed

to

plug

directly

into

a

wall

outlet.

Additionally,

the

wallwart

style

base

station

220

can

use

the

Power

over

Ethernet

methods

for

communications

with

the

client

device.

In

this

manner,

the

base

station

220

can

be

easy

to

install

because

it

can

be

readily

plugged

in to

a

power

socket.

The

base

station

220

can

also

use

?ash

memory

or

rotation

media

to store

captured

data.

As

noted

above,

audio/video

data

can be

requested

by

the

client

application

system

through

the

network

260 and

ser

viced

by

a

virtual

web

server

222

in

the

base

station

220.

Typically,

the

remote

client

250

consists

of

computer

running

a

software

application

that

analyzes

and/or

stores

data

for

security

and

surveillance

purposes.

Multiple

cameras

can

be

connected

to

a

base

station

220

via the

wireless

link

240.

The

client

computer

can

in

turn

run

a

surveillance

application

to

access

the

connected

cameras.

The

client

application

can

query

the

virtual

web

server

222

in

the

base

station

220

using

standard

or

de-facto

APIs

such

as

those

available

from

Axis

communications.

In

particular,

the

base

station

code

can

com

ply

with

well

established

IP

camera

API’s

from

companies

such

as

Axis

communication’s

“VAPIX”API

or

similarAPIs.

In

one

implementation,

the

base

station

220

can

be

con

nected

to

the

Internet

through

a

cable

modem

or

a

DSL

modem.

In

this

manner,

the

IP

address

of

the

cable

modem

or

DSL

modem

can

be

dynamically

assigned.

The

constant

changing

of

the

IP

address

can

make

it

more

complicated

to

build

a

virtual

web

server

on

the

base

station

220

and

provide

accessibility

to

clients

on

the

Internet.

A

dynamic

domain

1 2 ... 13 14 15 16 17 18 19 20 21 22 23 ... 29 30

Komentáře k této Příručce

Žádné komentáře