摘要:
In a data transmitter having a data encoder, an encoder mode is detected. Thereafter, an excluded codeword output by the encoder operating in the encoder mode is identified. Next, a selected bit in the excluded codeword caused to have a predetermined value to produce a non-excluded codeword. Finally, the excluded codeword is substituted with the non-excluded codeword, wherein the non-excluded codeword is selected to mitigate effects of a decoding error in a receiver associated with the excluded codeword.
摘要:
The present invention provides a method and apparatus for improving the audio quality of a signal by reducing the effect of mis-determining the frame rate of a frame. The method includes the steps of determining that the frame rate of the current frame of information is eighth rate (324/340), determining that the previous frame was a full rate frame (334) and resetting the filter states of a speech decoder (336). The method further comprises the steps of utilizing alternative symbol error thresholds based on the number of consecutive frames with the same frame rate (308/328).
摘要:
A convolutional encoder (112) comprises a controller (201), having a transmission rate (e.g. frame rate) as an input. The controller (201) initializes the encoder (112) to an initial state based on a transmission rate currently being utilized. When decoding, a decoder (300) utilizes a Trellis diagram having an initial and final state based upon the frame rate.
摘要:
Because prior-art rate determination algorithms are prone to falsing, a sub-rate discrimination metric generator (160) is provided herein. The generator (160) correlates a received frame with known characteristics of sub-rate frames to generate additional metrics useful in rate determination. These metrics are passed to a modified rate determination algorithm (150).
摘要:
Upon receiving (101) a vocoded voice frame and detecting (102) that the received vocoded voice frame comprises an erased frame, one automatically replaces (103) the erased frame with a valid frame having at least one error condition. In a preferred approach this error condition is one that is known to cause a receiving target platform to invoke a corresponding erasure process with respect to the valid frame when received.
摘要:
An apparatus (18) and method (100) provide RLP data checking. The apparatus (10) includes a frame serialization stage (20) and a bad frame filter (22) that detects possible bad frames and reclassifies these bad frames as erasures. In this manner, bad frame data are not passed to the RLP layer (16), and unnecessary resetting and resynchronization steps are avoided.