question about radio-communication?

[nick]

if i have a transmitter(T) ,receiver(B,C,D) in Room (X)
(T) transmit a signal to (B,C,D) at the same frequency, but at
different channel, so that (T) can control (B,C,D) individually.
Room(Y) is nearby Room(B), i use the same set of above in Room(Y),
then Room(X)and Room(Y) ,use that system at same time , the signal of
(T) in Room(X) will transmit throught the wall and enter Room(Y).so
how to solve this problem?

like the radiotelephones ,in a flat every families can use the same
model radiotelephones , but the phone signals will not against each
others?

Sorry, my english is not good,so if the above explanation is not
clearly, i very welcome you ask me to explain again

thank you very much!

 

[Rich Webb]

if i have a transmitter(T) ,receiver(B,C,D) in Room (X)
(T) transmit a signal to (B,C,D) at the same frequency, but at
different channel, so that (T) can control (B,C,D) individually.
Room(Y) is nearby Room(B), i use the same set of above in Room(Y),
then Room(X)and Room(Y) ,use that system at same time , the signal of
(T) in Room(X) will transmit throught the wall and enter Room(Y).so
how to solve this problem?

like the radiotelephones ,in a flat every families can use the same
model radiotelephones , but the phone signals will not against each
others?

Because magic happens. Either there is a central controller that has
an off-band control channel which allocates resources as required to
eliminate interference or the users cooperate and agree to use
non-interfering channels.

In the case where there are never more than N systems within range of
each other, the systems could negotiate among themselves with discovery
and collision detection. As N gets large, a significant amount of
bandwidth is consumed on negotiation.

In your example above, the two transmitters would each need to be able
to receive the signals from the other and adjust their behavior
accordingly.

 

[Rich Grise]

if i have a transmitter(T) ,receiver(B,C,D) in Room (X)
(T) transmit a signal to (B,C,D) at the same frequency, but at
different channel, so that (T) can control (B,C,D) individually.
Room(Y) is nearby Room(B), i use the same set of above in Room(Y),
then Room(X)and Room(Y) ,use that system at same time , the signal of
(T) in Room(X) will transmit throught the wall and enter Room(Y).so
how to solve this problem?

like the radiotelephones ,in a flat every families can use the same
model radiotelephones , but the phone signals will not against each
others?

Sorry, my english is not good,so if the above explanation is not
clearly, i very welcome you ask me to explain again

Your English sounds like you very carefully used your Language-
to English dictionary, and did very well.

About your concern - it sounds like you have room X with transmitter
T, and receivers B, C, and D. T can control B. In room Y, you have a
transmitter (same set of above, right?) T, and receivers B, C, and D.
You're asking how, when guy X uses T to control B in X, he doesn't
want to control B in Y.

Is this pretty close?

What kind of choices are available for frequencies and channels on
the same frequency?

Would it be feasible to enclose one of the rooms in a Faraday cage?

Thanks,
Rich

 

[nick]

can i use a IC to detect the free channel automatically like the
radiotelephone? any IC or circuit can do that?

thanks