Recently, China Telecom has issued a tender notice for the centralized procurement project of Tiantong Mobile. According to the announcement, in order to cooperate with the successful operation of Tiantong Satellite Operation Service, it plans to purchase 100,000 Tiantong mobile phones, including 50,000 single-mode and dual-mode products. It is reported that the project has a total of 2 tenders, and the number of successful bidders is 1 for each tender. Bid 1: Single-mode (single-satellite communication) mobile phone, estimated purchase quantity of 50,000 units; bidding section 2: dual-mode (satellite + terrestrial communication) mobile phone, estimated purchase quantity of 50,000 units. According to the announcement, the project adopts the framework + order model, and the actual purchase quantity depends on the demand and sales, and is supplied according to the order. The quantity of the frame purchase and the estimated total amount do not constitute a substantial commitment, and only the actual purchase quantity accumulated during the contract period is used to settle the payment. It is worth noting that on May 16th, China Telecom “Tiantong No. 1 Satellite Mobile Communication†officially released the number to the commercial market, which marked China’s entry into the “mobile phone era†of satellite mobile communication and filled the domestic autonomous mobile communication system. The gap is breaking the current status of dependence on foreign satellite mobile communication services. On May 25th, China Telecom "Tiantong No. 1 Satellite Mobile Communication" was officially commercialized in Qinghai, realizing real commercial use. It is reported that in 2011, the "Tiantong No. 1 Satellite Mobile Communication" system project was officially launched. It is China's first satellite mobile communication system. After that, China launched the Tiantong-1 01-orbit mobile communication satellite, which is China's first mobile communication satellite with complete independent property rights. Since then, China Telecom has released a mobile phone based on Tiantong No. 1 - Tiantong No. 1 satellite mobile phone. The chip used by Tiantong Satellite Terminal is also produced by China. Tiantong Satellite has many advantages, such as wide coverage, strong communication capability and no blind spots in service. It has a very broad development space and can be applied to personal communication, marine transportation, ocean fishing, air passenger transportation, bipolar scientific research, international peacekeeping and other aspects. Support confidential voice communication, data transmission, video conferencing, disaster relief, maritime rescue, remote zone rescue, distance education, telemedicine, radio, live broadcast, etc., and also provide Internet access for high-end business users such as scientific research and exploration. Access, personal mobile communications and other services. Tiantong No. 1 ground service is operated exclusively by China Telecom, and together with the ground mobile communication system constitutes a mobile communication network, which can realize the whole territory and territorial sea and the first island chain in China; the surrounding areas of China, the western Pacific and the Indian Ocean are fully covered. Any corner of the motherland can communicate at any time, at any time, on demand.
Yuhai Company is engaged to research
and development of piezoelectric products
and related piezoelectric products, the related piezoelectric products includes the piezo sensors and transducer.
The ultrasonic transducer is a kind of transducer that converts the ultrasonic signal into electric signal, or vice versa. Ultrasound transmitter and receiver is a transducer that can transmit and receive ultrasound. Ultrasound sensor is a kind of sensor, in essence, it is also a transmitter and receiver. The working principle of this kind of equipment is similar to that of radar and sonar. Active ultrasonic sensors can emit and receive reflected waves, and determine the distance of the target by measuring the time interval between transmission and reception. Passive ultrasonic sensor is actually a microphone that can convert ultrasonic signal into electrical signal.
Ultrasonic Sensor,Piezo Sensor,Ultrasonic Piezo Disc,Ultrasonic Piezo Elements Zibo Yuhai Electronic Ceramic Co., Ltd. , https://www.yhpiezo.com
According to the working principle and materials used, the ultrasonic transducer has piezoelectric transducer, electrostatic transducer (capacitive transducer), magnetostrictive transducer, electromagnetic acoustic transducer, mechanical transducer and other types [1].