Post on 28-Nov-2015
description
Issue 0.0, 22/9/10 1/9
Domo Limited doing business as Cobham Surveillance www.cobham.com/domoDomo Limited doing business as Cobham Surveillance
The Use of MESH Technology inOutside Broadcast
Cobham SurveillanceDomo Products11 Manor Court,Barnes Wallis Road,Segensworth,Hampshire,PO15 5THEngland
T: +44 (0)1489 566 750F: +44 (0)1489 880 538
Mesh for Wireless Cameras and ENG Links
2/9www.cobham.com/domoDomo Limited doing business as Cobham Surveillance
Background
The purpose of this document is to describe how the MESH Radio system fromCobham (known as NETNode) can be used to revolutionise Electronic News Gathering(ENG).
Traditionally the ENG market has been satisfied by the use of many separate radiolinks. These links included the following elements.
1) Camera Back Solutions, wirelessly connecting the camera to the News truck.2) Talk back radios, allowing the truck to wirelessly communicate with the camera
man.3) Camera control radios, wirelessly allowing the truck to control the news
camera.4) ENG links, connecting the feed from the news truck wirelessly to the studio.5) ENG return links, wirelessly allowing the studio to communicate with the truck.
Traditionally all of the above have been separate RF links, on separate frequencies. Inthis document it will be demonstrated how all of these links can be replaced by a singlemicrowave system known as NETNode.
Issue 0.0, 22/9/10 3/9
Domo Limited doing business as Cobham Surveillance www.cobham.com/domoDomo Limited doing business as Cobham Surveillance
Introduction to NETNode
Cobham has developed a revolutionary IP MESH Radio System known as NETNode.The NETNode system allows up to 8 individual Nodes to share a single commonfrequency for bidirectional communication. Data can be IP, video, audio or RS232comms. These radios offer a MESH with capacity of 4Mb/s which will be upgraded to8 – 12Mb/s (due in 2010).
Cobham NETNode IP mesh radios are thelatest innovations in the expanding range ofCobham Surveillance solutions that featuredomo technology at their core.
NETNode IP radios can be combined in afluid self forming, self healing meshcontaining up to eight radios. The NETNoderadios within the mesh exchange data on asingle frequency, simplifying frequencymanagement. The entire mesh occupies just2.5MHz of bandwidth (3 and 3.5MHz alsoavailable). The NETNode radios employ theunique Cobham COFDM modulation schemeand therefore offer excellent RF penetrationand performance in the presence ofmultipath.
The NETNode mesh radios can provide up to3.5Mb/s of IP data (data rate depends onmode, number of nodes and range betweennodes). This available IP data rate can beused to exchange IP data traffic betweennodes.The highly flexible mesh topology means thatdata can be exchanged between nodes in apoint to point or multi-point fashion; rangecan be extended by using nodes asrepeaters. The self forming, self healingmesh architecture makes the NETNodeproduct ideal for use in mobile surveillanceapplications, command and control, oradvanced robotics.
The NETNode can be connected to third partycameras using the NETAV option. Alternatively,there are two dedicated PTZ camera solutionsavailable for direct connection to the NETNode:NETPTZ* is a high performance, high qualityday/night PTZ camera for long range and overtsurveillance; NETuPT is a miniature pan and tiltcamera suitable for up-close surveillance. TheNETuPT and NETPTZ* options require theNETAV option to be fitted.
Security of the entire mesh network can beensured by the use of the optional AES128 orAES256 encryption.Control of the deployed mesh is achieved usingthe inbuilt web browser or comprehensiveMesh Commander* PC application. Thissoftware suite, based around a mappingdisplay, is used to configure and monitor themesh, and to control its nodes and cameras.Video can be viewed on the PC device usingthe Mesh Commander* software or, if IPHardware Decoder devices are employed, videocan be viewed on conventional monitors andrecorded on conventional recorders. Remoteusers simply wishing to monitor the network,control cameras or view video, can make use ofthe Mesh Viewer* application available forsmaller hand held devices such as PDAs.
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Domo Limited doing business as Cobham Surveillance www.cobham.com/domoDomo Limited doing business as Cobham Surveillance
Specification:
Interfaces
RF Interfaces(Antenna 1 and 2) SMA
Power LemoEthernet 1 RJ45
Ethernet 2 RJ45Control and misc I/O DType
Camera Lemo
Typical range
NETNode-P-217250 (1W) Non Line of Sight Light urban 500-700m
Line of Sight 40km+
RF Interfaces
Antenna 1 Switched transmit receive antennaAntenna 2 Receive only antenna
RF and modulationOutput frequency 340 to 470MHz, 1000 to 1500MHz,
2170 to 2500MHz,4500 to 5000MHz*, or 5500 to6000MHz*
Tuning step size 125kHz step
Output power +30 to 0dBm in 0.25dB stepsBandwidth 2.5, 3 or 3.5MHz
Mesh capacity Up to 3.5Mb/sModulation COFDM 360 carrier modulation
Carrier Modulation BPSK, QPSK or 16QAM (adaptive)
FEC rate FEC1/2Receive diversity Maximum Ratio Combining
Receive sensitivity -98dBm for most robust mode
IP interfacePrimary and secondaryEthernet electrical 100BaseT Ethernet
IP address allocation DHCP dynamic IP addressing
Video and audio Multicast VLC compatiblestreaming format RTSP Support
A/V input optionVideo input Composite or SDI (selectable)
Video format 525 or 625 (PAL or NTSC)Video encoding MPEG4
Quality User selectable quality levelVideo bit-rate 2.4Mb/s to 50kb/s (variable)
Resolution 704, 576, 480 or 352
Frame rate Self selecting 30 to 2F/sStills capture feature HiRes JPEG file
Audio input Line level or microphone levelAudio sample frequency 48KHz
Audio encoding MPEG audio layer 1 G726Audio bit-rate 384 to 64kb/s
Store and forward options*
Storage format SD card interface (Secure Digital card)Record options Continuous or triggered
Files download From web browser interfaceVideo and audio clip size 30 seconds
Open Audio comms channel (shared voice channel)
Multi-user audiocomms channel Interface microphone level/headphone o/pCompression G726 32kbit audio
Encryption
Type AES128 or AES256 (both optional)
GPS
Dedicated GPS interface RS232
Data interfaceRS232/RS485 data input 1K2 to 115K2 baud switchable(shared with user camera With UDP and TCP routing protocolcontrol)
PTZ camera interface (with AVI fitted)User camera type PAL or NTSC
User camera control From Mesh Commander* PC applicationusing VISCA, PELCOD or PELCOPFrom any user supplied desk controllerRequires RS232 interface
NETNode bespoke cameras NETPTZ long range PTZNETuPT short range pan tilt
Triggers*
Trigger source Third party equipment remote trigger(e.g. ANRP, PIR, etc)User pre-set time triggerGeneral purpose trigger inputVideo motion detection (NETAV option)Audio level (NETAV)
Trigger action Start to transmit (silence mode)Activate video stream (NETAV option)Activate audio stream (NETAV option)Move camera to preset positionGeneral purpose trigger outputActivate local store feature
Control
Local control LEDs power and mesh statusRemote control Mesh Commander* PC application
Full control of all parameters in a map basedapplication
PhysicalSealing No IP rating - splash proof
Dimensions H 155mm, W 153mm, D 45mm
Mounting options base unit Through hole screwsWeight 1.24kg (including heat sink)
Power
DC input 12-14VPower consumed 1W 14W
Environment
Temperature range -10 to 50 deg C
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Domo Limited doing business as Cobham Surveillance www.cobham.com/domoDomo Limited doing business as Cobham Surveillance
Camera to News Truck Links
The NETNode IP MESH Radio can be used as a link from the camera to the news truckas shown below.
With a NETNode unit mounted on the camera, and a second unit mounted on thetruck, a non line of sight Bi-directional camera connection can be achieved. TheNETNode has excellent non line of sight propagation characteristics, and can achievelinks across a range of 350m to 800m non line of sight. This link can be used asshown below.
Bi-directional, singlefrequency communication.Typical Range 350m - 800mnon line of sight, or >5km Line of Sight
Camera withNetNode
News Truckwith NetNode
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Domo Limited doing business as Cobham Surveillance www.cobham.com/domoDomo Limited doing business as Cobham Surveillance
Audio Comms
Audio Comms
Camera Control
IP Video Editing
Video
Audio
Single FrequencyBi-directionalCOFDMCommunications
Video andAudio
CameraControl
NETNode on camera
NETNode in Truck
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Advantages of NETNode MESH as a Camera to News TruckLink
Using NETNode MESH radios as camera to truck links has the following advantages
1) Single frequency replaces, video link, audio talk back, and camera control,which are currently managed by three separate links.
2) Simplified frequency management, improved spectrum efficiency.3) Range can be extended by simply dropping additional links.4) Low delay video.5) Excellent non-line of sight performance.6) Direct connection of IP to IP editing suites improves quality.7) Simplified (IP) connectivity to satellite links for SNG.
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Onwards from News Truck to Studio
In applications where the News Truck is transmitting directly to a TV station (ENG),then the NETNode system can be used to extend the reach of the studio directly intothe News Truck and even onto the camera itself.
Single FrequencyNetwork Operatingbetween camera,News truck and NewsStudio
Issue 0.0, 22/9/10 9/9
Domo Limited doing business as Cobham Surveillance www.cobham.com/domoDomo Limited doing business as Cobham Surveillance
Advantages of NETNode MESH as a Camera to News StudioLink
Using NETNode MESH radios as a single frequency network from the camera to thestudio has the following advantages
1) Extends studio network to the truck, enabling shared IT infrastructure.2) Enables edited file management from the truck.3) Saves cost by enabling management of contribution direct from the studio,
including camera control and talk back.4) Single frequency replaces, video link, audio talk back, and camera control,
which are currently managed by three separate links.5) Simplified frequency management, improved spectrum efficiency.6) Range can be extended by simply dropping additional links.7) Low delay video.8) Excellent non-line of sight performance.9) Direct connection of IP to IP editing suites improves quality