37results about How to "Synchronization is stable" patented technology

Disclosed is a system and a training sequence setting method for performing frame synchronization in a wireless communication system. A received signal is affected by a frequency offset due to an oscillator mismatch between the transmitter and the receiver, which is one of the main causes of performance degradation of frame synchronization. In a prior Constant Amplitude Zero Auto-Correlation (CAZAC) sequence, the larger the frequency offset becomes, the more conspicuously the performance degradation of the frame synchronization occurs. The proposed training is designed to maintain a prior CAZAC property during a differential detection so as to perform a differential detection-based frame synchronization sequence insensitive to the frequency offset. As a result of performance verification, the proposed training sequence indicates that its performance of the frame synchronization is irrespective of the frequency offset, and has a better performance than the prior CAZAC sequence and random sequence.

The invention discloses a crawler type length counting device comprising two synchronous belt mechanisms. The two synchronous belt mechanisms arranged in an up-down mode are used for clamping a measured object, wherein the center distances are equal; portions, between the two pairs of front and back synchronous belt wheels, of clamping sides of the synchronous belts of the upper synchronous belt mechanism and the lower synchronous belt mechanism serve as clamping and contact segments; and pressure exerting mechanisms that are capable of exerting positive pressures on the clamping and contact segments towards the direction of the measured object are arranged at the inner sides of the upper synchronous belt mechanism and the lower synchronous belt mechanism. According to the invention, the pressure exerting mechanisms are used for exerting pressures on the clamping and contact segments of the synchronous belts, so that the clamping and contact segments can clamp the measured object all the time under the pressure effect. Therefore, the slipping phenomenon can be avoided and thus the stable synchronization performance can be realized during the whole metering process, thereby improving the length counting precision. Meanwhile, the running of the whole mechanism becomes smooth and stable, thereby substantially reducing the influence on the length counting precision by shaking.