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janu203
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When we use pulse code modulation , it is said that the min bandwidth requirement is half the transmission rate. Transmission rate given in Bits/sec. But why?
So that means we can represent binary '1s and 0s' with two distinct pulses which combine to form one period. and taking inverse of that period '1/2T' gives us minimum bandwidth.Windadct said:The short answer is Nyquist theorem...
In a binary signal ( 0/1) the highest frequency that can be represented (inverse of the period), requires 2 samples.
Nyquist theorem is fundamental, and well worth the effort to study specifically, and IMO - be able to relate it to 3 real examples to get a handle on it. It is not a difficult concept.
In pulse code modulation (PCM), the bandwidth is half of the transmission rate because each sample in the PCM signal is represented by a binary code, which can only have two values (0 or 1). This means that the signal can only transmit half of the information as compared to an analog signal with a continuous range of values.
PCM reduces the bandwidth compared to analog signals by sampling the signal at regular intervals and representing each sample with a binary code. This reduces the amount of information being transmitted, thereby reducing the required bandwidth.
The bandwidth limitation in PCM is not necessarily a disadvantage. While it reduces the amount of information that can be transmitted, it also allows for more efficient and reliable transmission of data. Additionally, advancements in technology have allowed for higher transmission rates, making the bandwidth limitation less of a concern.
The bandwidth in PCM can be increased by using higher sampling rates and more bits to represent each sample. However, this also increases the amount of data being transmitted and may require more advanced technology and processing power to decode the signal.
PCM has various applications in telecommunications, audio recording, and data transmission. It is commonly used in telephone systems, digital audio recording, and digital television broadcasting. It also plays a crucial role in digital data transmission over networks and the internet.