help on RF data transmission

[kumeemb]

Hi all,
I am into a project of designing a remote control for a crane. I have to continuously send data from transmitter(remote control ) to crane(reciever) , in order check an emergency situation. i new to RF designing. the biggest problem i have is that in area of application there is magnetic interference which can make my watch to run faster than normal.
I am not sure of, what means of communication should i use.
If i am going to use RF won't the interference affect the RF communication.
please suggest me something about
1) what type of wireless communication should i use (IR is not possible)....
2) what frequency should i use
3) can you suggest me some design or some circuits to implement.


regards,
Kumeemb

 

[khouly]

u can use the ISM band there are alot of IC for TX and RX for ISM band like 926 MHz , 2.4 GHz , 433 MHz
check www.ti.com , the chipcon products u will find alot of information

khouly

 

[kumeemb]

Thanks a lot. that was useful.......
But the application that i need requires just 5 m distance of operation . do you think this is enough or i can go for something cheaper.
regards,
Kumeemb

 

[khouly]

if u need something cheaper , go to micorchip

they have many ISM band TX and RX

khouly

 

[kumeemb]

hi
thanks . well i am worried about the interference present in the field. can you please tell me whether interference would affect ISM band transmission....
if yes can you please suggest me some possible solution

regards,
Kumeemb

 

[khouly]

in the 900 MHz , and 2.4 GHz are the most interference coz in 900 there is a GSM operates near this band , and in 2,4 u have BlueTooth , Zigbee , WiLAN ,

avoid them by using some high quality filters , i am not sure what to else

khouly

 

[rogerynt]

Interference caused by frequency hopping system cannot be filtered ( Unless your system has the same hopping scheme. )

I will choose 900Mhz ISM band rather than 2.4Ghz because

a.) More and more consumer electronic products use 2.4Ghz rather than 900Mhz so that 900MHz becomes much ' quiet '.

b.) Bluetooth plue other frequency hopping system operate in 2.4Ghz cause serious jamming.

For 900MHz band,

a.) analog cordless normal select frequency near band edges.

b.) Direct Sequence Spread Spectrum system : non frequency hopping system therefore careful frequency planning helps to avoid jamming. ( Operation frequencies DSSS system are chipset dependent. Can be found out )

c.) Since you are discussing 900MHz ISM band therefore I expect your system is operating in US etc countries therefore the effect of GSM jamming is limited. ( I assume )

d.) Frequency hopping system, as described early, 900Mhz has less interest to general public because people think the higher the frequency the better the performance therefore companies will spell less resource to invest for 900MHz band system ( money issue ) so less jamming.