Method and apparatus providing protection and DC balance in a communication system

摘要

A method and apparatus for controlling DC balance in a digital communication system in which data frames are transmitted, wherein the data frames include a header portion that is transmitted unscrambled and a payload portion that is scrambled before transmission. The header portion includes a frame counter field. A value for the frame counter field is randomly generated and an effect on the DC balance is estimated. It is then determined whether the estimated effect on the DC balance meets defined requirements for DC balance. When the estimated effect does not meet the defined requirements for DC balance, a new random value for the frame counter field is generated and checked. When the estimated effect meets the requirements, the randomly generated value is utilized in the frame counter field in transmitted data frames.

主权项

1. A method of controlling direct current, DC, balance in a digital communication system in which data frames are transmitted, the data frames having a header portion that is transmitted unscrambled and a payload portion that is scrambled before transmission, the header portion including a frame counter field, the method comprising the steps of:
a) randomly generating, by a random number generator, a value for the frame counter field; b) estimating an effect of the randomly generated value on the DC balance of a frame; c) determining whether the estimated effect of the randomly generated value on the DC balance of the frame meets defined requirements for DC balance; d) when the estimated effect of the randomly generated value on the DC balance of the frame does not meet the defined requirements for DC balance, repeating steps a) through c) until the estimated effect of the randomly generated value on the DC balance of the frame meets the defined requirements for DC balance; and e) when the estimated effect of the randomly generated value on the DC balance of the frame meets the defined requirements for DC balance, utilizing the randomly generated value in the frame counter field in the transmitted data frames.