Been researching wireless solutions to transmit in real-time sensor and decision information from ART in addition to possibly enabling minimal controls (on/off/behavior switch) and perhaps even wireless firmware updates.
My criteria:
- Low-cost (<200RMB, preferably <100RMB)
- Simplex or half-duplex OK
- Low-bandwidth (>1,200 bit/s)
- Low-power (<100 mAh)
- Medium-range (500m-1000m)
- TTL or SPI interface
One of the main issue is that I cannot find a clear reference to the spectrum allocation in China (The US has a very convenient Frequency Allocations Chart: http://en.wikipedia.org/wiki/Frequency_allocation).
I know that 2.4Ghz is good worldwide (such as what the Nordic nRF240L uses) but that has a very limited range (50m-100m). So is Bluetooth and to a certain degree Wifi (and they are pretty expensive too).
There are these:
- PTR8000+ [Nordic nRF905 (433/868/915MHz)]
- Laipac Tech RF 900DV(900 mhz)
- Laipac ASK Transmitters (315 mhz)
- Databridge
- http://www.starmanelectric.com/OrderDataBridge/tabid/71/Default.aspx
- http://www.starmanelectric.com/LinkClick.aspx?fileticket=REf/38lk/L4%3d&tabid=75&mid=456
- Expensive (87$USD) and not available here?
- JZ871 Data RF transceiver for wireless telemetry system (433 MHz or 868Mhz/915Mhz)
- http://www.alibaba.com/product-gs/252550553/RF_data_transceiver.html
- http://www.jizhuo.com/download/product_images/f/cn_f__101.pdf
- I’m guessing if Alibaba is selling it, it’s ok in China? Or is it exactly just an export product?
Last one actually looks better than the Nordic on paper, but from what I gathered the price is pretty high. I wonder about the price and why I can’t find it on Taobao…
I’ve used the databridge modules from starman electric (www.starmanelectric.com), and they are very easy to setup for this type of application. They wern’t the cheapest, but they worked great and I got them up and running within a few minutes vs a few hours of frustration with other modules. I’m located in Germany, and my order was shipped from the US with no problem. I’m sure they will ship to China too.
Sam
Sam, thanks for the info.