My problem is that I cannot find any module that provides me with signal strength
did you look at the datasheet for the module i linked to?
pin 3 on the RX: "Received Signal Strength Indication - Analogue".
i just had a dig around on DigiKey for you and it turns out most cheep RF modules do not have RSSI pins.
the more expensive ones are more likely to.
and most of the transceivers do. (transceiver = 2 way RF module.)
so it looks like you are out of luck for getting a simple annalouge power reading unless you are willing to throw more money at it...
Google yielded these results :
It seems like I can change around the inductor and capacitor setting for my application.
heh, building your own RF tuners would be one way to do it but it it is a bit of a black art.
it would be possible but out of my field of expertise.
you might want to consider spending a few months lurking on some ham radio forums to pick up pointers.
in other news, last night i had a play around with the 2.4GHz modules i am using in my UAV project.
moving a receiving station round my house the reception was very non-linear.
for example i found one spot 2 rooms away from the transmitter with around 5% power level. 10 cm away in any direction i had 85% power level.
that was at 2.4GHz though.
things would probably be less polar at 315MHz.
remember when you were asking about the 2 Data pins on the RX module? how did that work out? are they just connected together like the datasheet suggests? (measuring the resistance between them would give you some indication.)
if they are not directly connected, get your multimeter and test the voltage on that pin as you move away from your transmitter. you might be lucky and it may be a signal test point. or better still a RSSI pin....
if i were you here is how i would proceed with your current modules:
it would be easy to test for successful packet transmissions. (idea 1 on your list.)
write a program that sends a packet every few ms.
in the packet have a long int which increases by one with every packet sent.
on the receiver subtract the value contained in the previous packet from the newly received one.
this will tell you how many missed packets there have been since the last successful one.
move it round the room and see what happens.
something else that comes to mind, with the RF modules i am using just now i actually get worse transmission results at very short ranges than at around 10meters.
my RSSI is high at close range but there is data corruption due to the RX module being flooded by too high a signal level.
this may or may not be an issue for you as my RF modules are quite high power.
got to get back to work.