Difference between A law and U law
A law vs U law:
A law and U law being two algorithms which are utilized in telephony systems over the globe, it is very easy to confuse these two terms with each other. Yet, A law and U law do have some significant differences which set them apart.
What is A law?
A law algorithm can be defined as a standard compounding algorithm which is utilized in the process of optimizing and modifying the dynamic range of an analog signal for digitizing. This is an algorhithm that is widely used in European digital communications systems.
Because of the fact that linear digital encoding does not serve well with the wide range of speech, the following code was introduced which results in the coding efficiency and reducing the varying ranges of the signals.
What is U law?
The U law algorithm too can be defined as a standard compounding algorithm which is utilized in the process of optimizing and modifying the dynamic range of an analog signal for digitizing. This system is widely used in north America and Japan. Whereas in analog systems, it increases the signal-to-noise ratio (SNR) during transmissions, in digital domain, it reduces the quantization error increasing signal to quantization noise ratio in turn.
This algorithm too is used because of the diverse ranges of the speech and because of the need to preserve the finer details of this range during communication. The u law encoding aids in reduction of the dynamic range of the signal which in turn increases the coding efficiency at the same time biasing the signal in a way that gives out the result in a signal-to-distortion ratio.
What is the difference between A law and U law?
Dynamic range can be defined as the smallest and the loudest sound that are represented by the signal. Therefore, the main difference between A law and U law can be defined in terms of the dynamic range output of the two algorhithms. Whereas U-law has a larger dynamic range than a-law, the dynamic range of A law is quite low. Yet, a higher dynamic range leads to greater distortion of small signals. Therefore, it is advisable that when the sound input is very soft, A-law is the best algorithm to be utilized.
Also, with regards to the countries that utilize a law and U law, the two algorithms vary. Whereas A law is widely used by European digital communication systems, U law is used widely throughout North America and Japan. While there are no significant differences between these two algorithms, these are the only distinctive factors which set them apart.