The military-industrial scientific research system of the academic master.

The S band is a very common signal source.

From radio communications to search radars to measurement and control networks, the S band may be used.

Of course, passive reconnaissance must be able to identify the nature of the signal.

Otherwise, you will find radiation sources everywhere, and there will be no point in "reconnaissance".

As the latest strategic reconnaissance drone of the US military, the Global Hawk can directly display the direction and characteristics of the received signal on the screen of the equipment operator.

For example, in the S band, the signal coming from the eastern lower hemisphere 100 kilometers away has a pulse width of hundreds of MHz and is powerful enough to burn through ordinary jammers. It is obviously a search radar in operation.

But the new signal just detected came from almost directly above the plane, with a pulse width of only single digit MHz and very weak power, which meets all the characteristics of a radio communication system.

Considering that the drone was flying at an altitude of 1.7 meters at the time, it seems unlikely that there happened to be a plane at a higher altitude.

Therefore, the operator concluded that this was a signal from a communications satellite, which was actually not a problem.

Ted Lynch also quickly adjusted the course from 110 to 40, which means flying northeast basically along the direction of the border line.

As a veteran reconnaissance pilot, even though he is no longer in the cockpit, he still maintains due caution.

Especially in Central Asia, a complicated place like this.

After flying for five minutes as promised, Lynch turned to look at his partner next to him:

"How's it going? Is it over?"

Although there is almost no concept of control radius for drones equipped with satellite communication antennas, it is flying in Kyrgyzstan's airspace after all, so he still hopes to try not to deviate too much from the route notified in advance.

In addition, the superiors also set a time limit for task execution in advance.

The mission area must be evacuated before 1 a.m. local time (5 a.m. Beijing time).

However, the other party hesitated for a moment:

"It would be best if we could turn around and fly again."

"Ah?"

Lynch's hands almost shook.

"This signal... is a bit strange."

The operator frowned and took a sip of coffee:

"Although the characteristics meet the requirements for satellite communications... the analysis results are too simple. It doesn't seem like any useful information is being transmitted."

Another advantage of Global Hawk is that it has achieved real-time intelligence analysis to a considerable extent by relying on high-throughput data links and ground-based supercomputers.

Even if the specific communication content cannot be deciphered, the communication capacity can be used to determine whether the analysis object is a false signal.

This function was actually prepared for wartime electronic reconnaissance, but it just happened to be used in the current environment.

Considering that there is almost no possibility of forgery of satellite communication signals, and that it is actually a very time-consuming task for such a large straight-wing aircraft to make a 180° turn, Lynch was somewhat reluctant:

"But they only asked us to capture unfamiliar satellite signals in this area, and they didn't provide any information about the characteristics of the signals?"

For a moment, the control room fell into silence.

In fact, this mission seemed very strange from the very beginning.

Most of the time, as pilots of strategic reconnaissance aircraft such as Global Hawk, they have the authority to understand more specific situations and can even make appropriate improvisations during the mission.

But today, they were basically just given a simple requirement of "where to go and what to find", so when faced with unexpected situations, disagreements could easily arise among crew members.

Due to the special nature of unmanned reconnaissance aircraft, the captain in charge of the flight does not have the final say, and in many cases the needs of the reconnaissance mission will prevail.

In the end, Lynch chose to compromise.

"All right……"

As he spoke, he began to carefully adjust his flight attitude, preparing to repeat the previous flight path...

However, just as he completed the turn and was about to return to his previous route, the operator next to him suddenly sat up straight.

I almost spilled the coffee in my hand.

Lynch looked at the other person with some doubt.

The latter stared at the screen in front of him:

"The signal...suddenly disappeared?"

……

Almost at the same time.

Somewhere in western Xinjiang Province.

Inside a 54K6E2 air defense command vehicle, Zhu Xuejun, wearing a cotton coat, was sitting in front of the operating console, staring intently at a target track on the screen in front of him.

About 50 meters away, a 64N6E radar was working in a low-key manner.

This is a large-scale battlefield management radar that is only assigned to brigade/regiment level command, which can greatly reduce the workload of the 64N6E search radar.

As for the launch sites, they are deployed further away.

The reason for this arrangement is mainly to prevent all combat capabilities from being destroyed at once by anti-radiation means.

Zhu Xuejun, who was just a brigade commander four years ago, now has a star on his shoulder because of his repeated participation in major tactical and combat verification and training missions.

And his old unit, the former Jincheng Military Region Air Defense Mixed 4th Brigade, has now been upgraded to the 4th Surface-to-Air Missile Brigade.

However, because he was still in the adaptation period after receiving the new equipment, Zhu Xuejun, who had already joined the Jincheng Military Region Air Force, returned to his old unit and was responsible for the research and training of new tactics.

This was originally just a normal work process, but at this moment it brought an unexpected benefit -

Zhu Xuejun has the authority to make many decisions that brigade-level officers are unable to make.

This is equivalent to reducing an intermediate command link.

"Chief of Staff, orders from above."

The correspondent came to the command vehicle in a hurry, holding a draft in his hand:

"Maintain surveillance and tracking of the target. If the target is still lingering nearby at around 5: Beijing time, issue a warning to it."

"it is good."

Zhu Xuejun nodded calmly.

Under the current circumstances, it would be inconvenient for the air force to be deployed.

Then they can only rely on their ground-guided forces as the last line of shield.

But the new brigade commander Fan Rongjian, who was sitting next to him, could not sit still:

"Chief of Staff, we are using missiles... How do we send a warning..."

The air force can accompany, interfere, use infrared decoys, and even use machine guns for warning shots.

But once an air defense missile is launched, it cannot be taken back.

Besides, the other person was flying overseas the entire time, so it would be completely unreasonable to even just lock on to him, let alone make a call.

Zhu Xuejun hesitated for a moment and did not give an answer immediately, but continued to ask:

"Electronic reconnaissance battalion, still no signal detected from the target?"

"No, the target remained silent throughout."

Fan Rongjian shook his head and gestured towards the radar screen:

"At present, we can only speculate based on the trajectory detected by the radar that the other party may be a newly commissioned RQ4A Global Hawk drone."

"call--"

Upon hearing this speculation, Zhu Xuejun let out a long sigh and his expression became solemn.

There was no active signal, and it was late at night, which meant that there was a high probability that passive electronic reconnaissance was being carried out.

In this situation, if you react violently, you will only help the other party achieve their goal.

But he couldn't do nothing.

Finally, I had to choose a compromise:

"Have the 30N6E radar ready. We can start a test when the time comes, but it must be short so that the enemy cannot capture too many signal features..."

One disadvantage of imported equipment is that the frequency of small upgrades and updates cannot keep up.

Therefore, more attention should be paid to confidentiality.

"Yes!"

Fan Rongjian saluted, then turned around and began to communicate with the 1st Air Defense Missile Battalion deployed on the westernmost side.

At this time, the target displayed on the radar had completed a slow 180° turn, and seemed to be preparing to repeat the original route.

"TMD..."

Seeing the Americans who seemed to be still unsatisfied, Zhu Xuejun couldn't help but swear under his breath.

Although the Chinese military, especially the Air Force, has been updating its equipment at a fairly high frequency in recent years, there is still some gap compared to its powerful enemies.

For example, this Global Hawk flying in the sky has no other model to compare with.

What is even more troublesome is that others have too great an advantage in terms of geography.

It may not seem like much when you look at it on the map.

But if you put it on a globe, you will find that there are US military bases almost everywhere around China.

In a situation like today, the other party is clearly here for reconnaissance and provocation, but there is no problem at all under international law.

No matter how you deal with it, you will only suffer in silence.

Thinking of this, Zhu Xuejun's thoughts flew back to a few years ago -

Although he still doesn't know the full story, the technology he tested appeared abroad in the blink of an eye and achieved world-shocking results. At the same time, the opponent's precision-guided weapons made a bizarre mistaken bombing...

It's hard not to connect the dots.

As a soldier, he understood the requirements of confidentiality regulations and never told anyone about his guess.

But faced with this situation, Zhu Xuejun couldn't help but start thinking.

In peacetime, there is almost no room for maneuver in the use of surface-to-air missiles or fighter jet interception.

Besides, when it comes to air defense, nine out of ten defenses will fail.

No matter how advanced the air defense system is, if it only responds passively, loopholes will appear sooner or later.

And if we can find a way to disrupt or even mislead the other party's route...

Seems like a more viable way to fight back...