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The power usage of a WSN system will be dominated by the radio RX and TX, not so much the sleep current.  So it doesn't really matter.  I would use the 5529 instead of the FR5969, if only because it is more capable.  It runs faster, too, which can be important if you have a protocol with even the slightest degree of sophistication.  That said, the MSP432 launchpad is the best choice IMO.

 

The energy usage of sensor node is dominated by the power consumption of MCU and RF module when the duty cycle is high, i.e. the node transmit many packets per a minute.

 

But when duty cycle is very low and the node transmit a packet say every 10 minutes, then the energy usage is dominated by sleep current of these units. Thus, the total sleep current of the sensor node is very important in low rate WSN applications. 

 

average power consumption =  active  power * duty cycle + sleep  power * (1 - duty cycle)

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A typical duty cycle for a WSN endpoint is between 0.1% and 1%.  Yes, it can be lower if you are doing only transmissions at scheduled intervals, but this is not very functional.  I don't know if you

Check out http://forum.43oh.com/index.php?/topic/8274-Cheap-solar-battery-%2B-wireless-IoT-node     Sent from my iPhone using Tapatalk

I'm pretty sure that there is little to no overlap between CC1120 and CC1101.   CC430 has the same radio core as CC1101 afaik     Sent from my iPhone using Tapatalk

The energy usage of sensor node is dominated by the power consumption of MCU and RF module when the duty cycle is high, i.e. the node transmit many packets per a minute. But when duty cycle is very low and the node transmit a packet say every 10 minutes, then the energy usage is dominated by sleep current of these units. Thus, the total sleep current of the sensor node is very important in low rate WSN applications....

 

A typical duty cycle for a WSN endpoint is between 0.1% and 1%.  Yes, it can be lower if you are doing only transmissions at scheduled intervals, but this is not very functional.  I don't know if you are using someone else's protocol stack or if you are building your own, but I know all the major stacks, and all are at least 0.1% duty cycle.

 

Even in the 10 minute beacon case, if you are using low data rate to get long range, you will use more power in TX than sleep.  "Back of the envelope" I calculated 4uA average current, which is more than the sleep current.  The MSP432 can sleep at 1uA, the 5529 at 2uA, and the 5969 at something like 0.5uA.  Really, this is a "drop in the bucket."  I've been designing WSN for almost 10 years now.

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You're right, but for environmental monitoring to measure the pollution and some other parameters, it's common to transmit a sample of measured data every 10 minutes or even 30 minutes as listed in many papers in the literature.

 

I designed my own protocol suite, so I need optimized hardware in term of power consumption and I'm not interested in using the recent product for just to  keep up with the Joneses.

 

I see you have good experiences in TI products. Please can you tell me the most optimized and easy to use launchpad for my application.

 

Also I plan to reuse these launchpad in college lab for future graduate research works.

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Please can you tell me the most optimized and easy to use launchpad for my application.

 

 

I would use the MSP432 launchpad, because it has the best performance, the best low-power, and I am very familiar with ARM.

 

If you do not have experience with ARM, the 5529 launchpad will be the best choice.  This chip has much better support than the FRAM ones have, and it can run basically twice as fast.  Since you're building only a pilot project (you're buying launchpads), quibbling over 1.5uA is just plain dumb.  Increase the size of the battery a tiny bit, instead.

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Doesn't really matter, you'll just need to think about how much money that you want to spend and how that you will construct your test setup.

 

These radios are geared toward this kit http://www.digikey.com/product-detail/en/CC1200DK/296-36405-ND/4271561

 

The kit comes with CC1200 modules and you can buy the cc1120 modules for another $99

 

With these kits it will be difficultto use anything besides the built in MSP430F5438A.

 

Alternatively http://www.digikey.com/catalog/en/partgroup/cc1200-evaluation-module-kit-420-470mhz/40641 has pin headers that you can wire to whatever you want.

 

To kinda put it bluntly, none of the options are ideal because to develop and test sensor networks you need a lot of nodes and if each node costs you $50 or $150, thats a severe limitation.

 

Thats why I built my own cheap nodes http://forum.43oh.com/index.php?/topic/8750-New-MSP430-Wireless-Sensor-Node

 

Its hard to have your cake and eat it too

 

 

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Hello Lgbeno

There is no problem with the budget.

 

I really want to construct a sensor node using MSP-EXP430FR5969 and CC1120EMK-868-915 is that possible or need another piece of hardware.

 

Can I use Energia to program this node and take advantages of the features of this hardware like using EnergyTrace++?

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Hello Lgbeno

There is no problem with the budget.

 

I really want to construct a sensor node using MSP-EXP430FR5969 and CC1120EMK-868-915 is that possible or need another piece of hardware.

 

Can I use Energia to program this node and take advantages of the features of this hardware like using EnergyTrace++?

 

You're lucky.

Buy all of these:

 

http://www.digikey.com/product-detail/en/CC1120EMK-868-915/296-30208-ND/2749371

http://www.digikey.com/product-detail/en/BOOST-CCEMADAPTER/296-36889-ND/4379861?WT.mc_id=IQ_7595_G_pla4379861&wt.srch=1&wt.medium=cpc&WT.srch=1

http://www.digikey.com/product-search/en?KeyWords=MSP-EXP430FR5969&WT.z_header=search_go

 

and if you want to do cc1200, add this:

http://www.digikey.com/product-detail/en/CC1200EMK-868-930/296-36407-ND/4271563

 

Each node will cost you $95

 

You can use Energia with this setup but it is not plug and play by any means, you'll have to do a lot of work with writing libraries for the radio and your WSN.

 

EnergyTrace should be possible BUT I think that you need to use Code Composer Studio for this feature, someone who has tried it out can correct me if I am wrong.

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