In the course of transmission, mud pulse signal mainly disturbed by drilling pump, engine in the bottom hole, air bladder contained in mud and movement of drilling equipment.

泥浆脉冲信号在传输过程中主要受钻探泵、井底动力机、泥浆中的气泡及活动钻具的干扰；

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They contain a battery-powered pump and bladder, allowing the cylinder to control its buoyancy.

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