# D1101ET007DE IVC 21 July In cellular technology, each basesystem has cell-like shape to provide UP and DL from and to the UE ITB develop a basestation for remote area in Indonesia. The system architecutre still adopt traaditional deployment where BBU and RU is in one place. 
The system utilize 4G mobile broadband. The cable from RU to the base station is big and expensive. There are also lots of power loss due to the use of this cable. But the overall testing result is satisfactory. People and student can use the service to d streaming/ other internet activities. ## Introduction of information theory The roots of modern digital communication stem from ground breaking paper: a mathematical theory of communication by claude elwood shannon in 1948 Source -> Coding -> Communication channel -> decoding -> destination in communcation channel, there will be a noise that distort the information shannon wants to find a way to reliably transmitting data thorughtout the channel at maximum possible rate. Example of communication channel: air, disk, our self brain. Message do have meaning, but in communication, machines dont care about it. in shannons vision, the flow becomes: Data->Source encoding->channel encoding->channel->channel decoding->source deconding-> user source coding uses entrophy function to calculate how amny bits required to store probability informaation ## binary erasure channel is a channel with binary input and binary output and probability of error ## channel coding theorem reliable commiucation is possible if data rate is below C C = 1-p(packet loss) ## hamming codes Hamming codes are a family of linear error-correcting codes. Hamming codes can detect up to two-bit errors or correct one-bit errors without detection of uncorrected errors