In order to reach a frequency of 140g hertz, the vacuum traveling wave tube power amplifier carried by the Starlink-1 satellite needs to rise the voltage to more than 25 thousand volts, and a special power supply needs to be designed for this power amplifier, and a special cooling system needs to be designed and developed for this component, which takes up a lot of space, and this power amplifier also needs to start time, and the output efficiency is not very high.

After several years of research and development, Huaxing Group has matured in gallium nitride single device and space power synthesis technology, and Huaxing Group has also launched more than 20 ultra-wideband high-power amplifiers with different frequency bands and different powers.

On this basis, Starlink-2 has been developed, and in the past about 4,500 components and nearly 1,300 RF cables were needed on a satellite platform of the same size, now Starlink-2 only needs 348 components and 64 cables, freeing up more space, and R&D personnel have stuffed more transponders and propellants, and even laser communication equipment.

At the same time, the phased array antenna of the Starlink-2 satellite can digitally form 5,000 optical beams, adjust the satellite power, position, and sensitivity at any time as needed, and carry satellite equipment that can be reprogrammed and software upgraded, which is much smaller than the previous technical equipment.

In addition, this design has a service life of up to 12 years, which is longer than the previous Starlink-1 satellite.

Seeing these power devices, the representatives of the European Satellite Communications Company showed envy in their eyes.

At present, Europe is limited by the process of gallium nitride devices, and there has been a lack of gallium nitride solid-state amplifier modules with hundreds of watts of output power, but Ka-band devices can be made on gallium arsenide devices.

However, the European side is still in the technical test stage of Ka-band satellites, only two test satellites have been launched, and Ka-band transmission technology has been used in the inter-satellite link and the feed link, and the maximum reverse data rate can reach 300 megabytes.

However, Huaxing Group has now jumped directly to the W-band, and has successfully developed more advanced gallium nitride devices and the most critical power amplifiers, leaving many companies and R&D institutions far behind.

There is a saying in the field of electronic countermeasures: "In the final analysis, it is energy that affects the effect of interference." Due to the increasing requirements for interference efficiency, it is necessary to develop ultra-wideband and high-power interference transmitters, and the power amplifier, the core component of interference transmitters, has become the decisive factor restricting interference efficiency.

At present, the power amplifiers of electronic countermeasures equipment in various countries use vacuum tube technology or solid-state technology, and now Huaxing Group Co., Ltd. generously displays its own high-power amplifiers, which proves that the domestic military has begun to use electronic countermeasures in large quantities.

The communications and electronic countermeasures technology equipment used by the military in the country has left Eagle Sauce and Europe behind, and many members of the delegation already understood it in their hearts when they saw these power amplifiers.

Although I don't know how Huaxing Group did it, it is an indisputable fact that Huaxing Group has matured in the preparation process of gallium nitride materials and the design and manufacturing of devices.

One of the scientists in the Eutelsat delegation understands that there is at least a 10-year technological gap between Huaxing and Europe in gallium nitride material technology, and now it is Europe's turn to catch up in this regard.

However, the delegation was more interested in the new civilian terrestrial transceiver terminal equipment that China Satellite Communications Corporation had shown them.

In the past, Ka-band ground station satellite communication systems relied on indoor-to-outdoor configurations. The outdoor unit consists of an antenna and a block downconversion receiver that outputs an analog signal in the L-band, which is then transmitted to the indoor unit, which contains filtering, digitization, and processing systems, which is difficult to achieve in a small size and low power consumption.

Over the years, Yang Jie has gathered a large number of scientists and engineers to conduct research and development on handheld and portable terrestrial transceiver terminals, and he hopes to make the terminals as small as possible to reduce power consumption to avoid carrying bulky and expensive batteries, while also maintaining high-capacity data transmission to meet the needs of civilian vehicles and even handheld phones.

One of the biggest technical challenges is filters, because Huaxing has increased the frequency to an astonishing 100 GHz or more, and it is becoming more and more difficult to achieve the same rejection performance when the frequency is converted to 1 GHz Z IF and it requires increasing the number or size of the filters, and these filters are not cheap, usually costing $200 or more each.

In addition, the antenna and processor in the traditional satellite communication market are separated, and Yang Jie's requirement is that the digitization and FPga are as close to the antenna as possible, because the wider the bandwidth to be processed, the higher the required clock rate and device power consumption, and the cost is still too expensive if all GaN devices are used.

To address these receiver challenges, the traditional approach has been to use a superheterodyne architecture, which is to downconvert the high-frequency band to the L-band, and there may be an intermediate stage before downconversion to the L-band.

However, this method requires the use of large filters, a large number of devices and high power consumption, which cannot meet Yang Jie's requirements.

In this technical architecture, the high-frequency band is not directly converted to the baseband, but is first converted to the high-frequency frequency, and then fed into the direct conversion receiver, that is, a converter is added.

This converter has a large frequency range, and this IF can be placed between 5G and 6G Hz. The increase in IF frequencies from 1G to 5G hertz has made the mirror frequency range farther away than before, so the front-end filtering requirements are greatly reduced, and the simplification of front-end filtering is a very important factor in reducing the size of such systems.

The core technology in this converter system is a mixer technology, when the receiver receives a high-frequency signal after the input RF energy for amplification, after filtering the frequency band to 77 to 81 Hz, these signals into the mixer, the mixer uses an 82G to 86G hertz range of tunable 77G to 81G Hz band at 100 MHz down to 5G Hz.

The front-end filter handles the image rejection in the W-band, and the general suppression of out-of-band signals to prevent spurious signals from passing through the mixer, this filter was specially developed by Huaxing Group, but the filter requirements are reduced, so the size can be very small, and it can be easily completed with off-the-shelf cheap small filters.

At the same time, now the frequency of the mixer frequency conversion has been reduced to 5G Hz, which can be directly converted to the baseband, and now the mature silicon-based devices of civilian products have increased their frequency range to 6G Hz, that is, the silicon devices of civilian consumer-grade communication devices can meet the needs of the previous ultra-high-performance military and commercial systems by using this technology.

On the transmit side, only a small GaN power amplifier is needed to amplify the RF energy to a 5 GHz waveform, which is of course different from the frequency on the receiver, mainly to reduce the possibility of crosstalk between the two channels.

The output is then filtered to reduce harmonic levels, and then fed into an upconversion mixer that converts to a 77g to 81g Hz front end.

This technical architecture has broken the barrier between satellite communication ground terminal equipment and civilian consumer devices at once!