HW projects - Outdoor wireless webcam server setup for two USB cameras

Components used: (for single unit)

-Icamview Pro webcam server (HW: HCV91) by Megatec
-A-Link WL54USB-A WLAN USB dongle (based on Atheros ZD1211 chip)
-Two ACME T071 USB webcams (based on Vimicro VC0301PLH chip)
-Two aluminium outdoor surveillance camera enclosures
-Weather resistant IP 66/67 enclosure with transparent lid by Fibox
-Two 52mm infrared LED clusters by Kingbright for night vision
-Small 4 port USB hub
-Two AC receptacles for fixed installation, a rubber AC cable & plug
-Few pieces of aluminium, cable ties & screws for installation fixture


Setup:

I assembled two identical units, but only one is equipped with night vision. Setting this up was a real pain in the ass since the Icamview Pro webcam server module supports only a handful of external USB peripherals. Basically the only supported USB camera chips are Vimicro VC030x (or ZC030x), ZC0323 and their variants (P/PL/PLH etc.). These cameras can be really hard to find, because the manufacturers don't usually bother mentioning what chip they are using in their products. The USB WLAN dongle needs to be based on Atheros ZD1211 or Ralink RT2500 chipset. Also, a USB hub must be used in this setup since the server has only two USB ports. All this was assembled to a pretty small enclosure.

Operation:

Due to the very limited range of a regular WLAN connection, the distance between the wireless access point (in this case Linksys WRT55AG Buffalo AirStation WHR-HP-G54 flashed with DD-WRT) and the webcam server cannot exceed 50 metres. Although, with a special directional WLAN antennna I have managed to get a connection from distances up to 100 metres, but at this point the signal starts breaking and it cannot be considered to be very reliable anymore. Increasing the range can quite easily be done using WLAN range boosters or repeaters but was not necessary in this case since the distance needed was only about 30 metres. It is also possible to use a wired LAN connection, if available.

The cameras I use are based on Vimicro ZC301PLH chip and it seems that this processor cannot adjust the exposure for bright environment and performs quite badly in outdoor conditions. Fortunately there is no direct sunlight in areas where the cameras are currently located. It seems that the Vimicro ZC0323 camera processor has an auto exposure feature that should fix this issue but I have not yet located a camera equipped with this chip.

Night vision:

IR LED clusters

Night vision is accomplished by using two infrared LED clusters. They draw 250mA of current per unit, totaling 500mA (~4 watts). It was not possible to remove the IR filter from the cameras that were found to be compatible with the server, so I had to swap the lenses to be modified from some unbranded cheap cameras that had somewhat same sized optics. Removing the filter has some downfalls, one of them being possible degradation of colors (especially if there is a lot of sunlight and when the IR illumination is on). The filter should not be removed if infrared nightvision is not needed.

Well then, why all this trouble?

There is a bunch of wireless surveillance cameras out on the market but they are all far from being low budget solutions and are rarely suited for outdoor use. I also used to have a dedicated PC running as a webcam server, but there are few good reasons why this is not so good idea:

-A single PC can usually host only one USB web camera.
-In the long run it is not the most maintenance (or crash) free way to go.
-Regular low end desktop PC draws from 40 to 200 watts of power, even when idling.

To see the system in action, follow this link: [ to webcam page ]

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UPDATE: 24/04/08 - Flashed both of the webcam servers with a new firmware (3.3.CV91.VER.8321) that i got from Megatec. The units jammed once in a week with the old FW, but after upgrading to this new version they seem to work perfectly.

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UPDATE: 11/05/09 - The IR power supply has been dead for a while now so I am going to power it straight from the USB. Camera 4 is currently being installed to a bird house with the IR cluster. Unfortunately it is a bit late as most of the birds have already settled for this summer.

parts used



finished unit