MASS-21 Echo Simulator of Radio Altimeter

The MDG-300 radio height-fixing device operates in the C-band and adopts a pulse compression system. Its sensitive component is of the heterodyne type, and the circulator at the antenna terminal uses a transceiver common-mode design. Prior to missile launch, the height-fixing device is powered on, and it undergoes self-check and height presetting via the communication interface. After the missile is launched, the radio frequency (RF) module is activated, and a gate is set in accordance with the preset height. When the preset height is reached, the device outputs height-fixing command information and telemetry data. The MDG-300 height-fixing device features mature technology: its pulse compression technology can enhance the altimeter’s height measurement performance, and it has the characteristic of a wide height measurement range. Additionally, the digital pulse compression function based on FPGA (Field-Programmable Gate Array) endows it with advantages such as small size, low power consumption, and low cost.

Operating in the C-band, the MY-70D radio altimeter employs a frequency-modulated continuous wave (FMCW) operating system and incorporates closed-loop tracking measurement technology, equipping it with the capability to resist same-frequency asynchronous interference. This ensures that when multiple aircraft take off and fly simultaneously, their altimeters do not interfere with one another. To achieve resistance against active interference, the altimeter adopts a range of measures, including anti-blocking, anti-burnout, power control, beam control, frequency agility, and frequency modulation (FM) technology. Furthermore, it features silent power supply control for its microwave components; its antenna is fitted with a band-pass filter, and a customized radome with frequency-selective functionality is utilized—these design elements enable the altimeter to achieve a wave transmission rate of ≥85% for the operating frequency within the band and less than 10% for out-of-band frequencies, thereby realizing stealth capabilities.

The MY-1000 altimeter is a radar altimeter specially designed for a specific type of target missile aircraft; as a compact, full-function radio altimeter that complies with aerospace standards, it serves as a key component for longitudinal altitude channel control and can be widely used in cruise missiles and UAVs to measure height relative to sea level or the ground. The MY-1000 adopts linear modulation coefficient technology adaptive to height changes and echo signal narrow-band receiving technology to enhance the product’s resistance to active interference, uses coherent local oscillator mixing to achieve superior performance in resisting co-frequency asynchronous interference, employs echo signal spectrum front detection technology to improve tracking accuracy, and follows the three design principles of serialization, standardization, and modularization—endowing it with good product inheritance, maturity, and reliability.

The MY-3001 series altimeters include models such as MY-3001A, MY-3001B, MY-3001C, MY-3001D, MY-3001E, MY-3001F, MY-3001G, and MY-3001H; as China’s smallest and lightest full-function radio altimeters that meet aerospace standards, they serve as key components for longitudinal height channel control and can be widely used in cruise missiles and UAVs to measure altitude relative to the sea or ground. The MY-3001 series altimeters adopt linear modulation coefficient technology adaptive to altitude changes and echo signal narrow-band receiving technology to enhance the product’s resistance to active interference, use coherent local oscillator mixing to achieve superior performance in resisting co-frequency asynchronous interference, employ echo signal spectrum front detection technology to improve tracking accuracy, and follow the three design principles of serialization, standardization, and modularization to enable high-speed production; additionally, built on a closed-loop tracking system, they integrate digital control technology, microwave integration technology, and hybrid integration technology to realize ultra-miniaturization of the product. As China’s first full-function radio altimeter, the series is known as the "high-speed rail ticket" in the industry.