Channel initialization method

An initialization method and channel technology, applied in the direction of digital transmission system, electrical components, error prevention, etc., can solve the problems of low transmission rate, small amount of data, and the transmission rate of logging system cannot meet the requirements, so as to meet the requirements of large data amount. Transmission requirements, the effect of increasing the data transmission rate
CN101202564BActive Publication Date: 2010-12-08CHINA NAT OFFSHORE OIL CORP +1
3 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
CHINA NAT OFFSHORE OIL CORP
Publication Date
2010-12-08

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

A channel initialization method includes the following steps: A1) a ground end modem and an underground end modem respectively send a first training sequence to each other; B1) the modem received the first training sequence finishes the training of channel activation, multi-carrier clock synchronization, multi-carrier symbol synchronization, multi-carrier frame synchronization, AGC parameter arrangement, transmission power adjustment, time-domain equalizer and frequency-domain equalizer; C1) the ground end modem and the underground end modem respectively send a second training sequence to each other; D1) the modem received the second training sequence carries out subchannel SNR estimation to the training sequence and carries out bit and energy distribution to each subchannel according to the estimated SNR value; E1) the ground end modem and the underground end modem respectively send a subchannel bit distribution information and a subchannel energy distribution information to each other.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention relates to a channel initialization method, in particular to a channel initialization method for well logging cables. Background technique

[0002] A logging system usually includes two parts: ground equipment (surface equipment) and downhole equipment (downhole equipment). The ground equipment and downhole equipment are connected by logging cables. The downhole instrument needs to transmit the collected data to the ground equipment through the logging cable; and the ground equipment also needs to transmit data such as control instructions to the downhole instrument.

[0003] Logging operations began in the 1920s to 1930s, and the logging system experienced development from analog to digital. At present, it has developed to the fifth generation imaging logging stage. With the development of logging tools, the demand for data transmission rate is gradually increasing.

[0004] In order to meet the increasing demand for data transmission...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More