FCC is federal communication comitee of USA. it is 
regulatory authority of USA like TRAI(actually DOT) in 
india.
Its role is to allocate frequencies from RF spectrum (1 HZ- 
300 GHZ) and providing licences for different application 
like TV, mobile comm., satellite comm. etc.

actually bluetooth works on a 2.4 GHZ ISM band which is an 
unlicenced band. hence FCC is not related to it much.

It is the process of temporarily storing the data to allow
for small variation in device speeds.

inband type of signalling is used between two exchanges

-48V

-48V DC for loopback
-48V AC for ringing

It will execute the non-maskable interrupt after the
execution of the current instruction.

Program Counter in a microprocessor (or CPU) is a pointer 
instruction of the program to tell where the CPU to look 
for the next instruction.

8 KHz

Nyquist Theorem: if you sample a signal in regular 
intervals of at least twice the highest channel frequency, 
the sample will contain enough information to accurately 
reconstruct the signal.
	Human Audible Range: 20 – 20,000 Hz
	Human Speech: 200 – 9000 Hz
	Telephone channel: 300 – 3,400 Hz
	Nyquist theorem: 300 – 4000 Hz 
	Sample size = (2 * 4000) 8000, 8000 * 8 bits = 
64,000 bps = 64 kbps

255

two hops

4

1/2 second

it is an IEEE standard, so interoperability was prescribed 
at the development phase.

frequency hopping is a spread spectrum technique in which 
the transmitter transmits at varying frequencies for very 
small periods of time say milli or nano sec. these 
frequencies are choosen in random among the frequency band 
available. the reciever and tansmitter both are aware of 
the sequence of the frequencies going to be used.
if some other agent tries to break the system and suppose 
tunes to a particular frequency then he'll be able to get 
that small part of the msg only because from next milli 
sec, the frequency is going to change hence through this 
wide band and secure transmission is achieved. 
used in bluetooth as well as in Wireless lans.
there are 69 frequency bands in bluetooth and hopping rate( 
rate of switching from one freq. to other) is around 1600 
hops/sec