We need to understand the concept of jamming

In general, we can say that while a communication link has only a single dimension that needs to be calculated (TX->RX), for the jamming case two dimensions need to be calculated (TX->RX and Jammer->RX) and then compared. The “link” that will present a stronger signal at the receiver’s input, will prevail; it can be either the transmitter (the “partner”) or the Jammer.
The Jammer’s role is to interrupt the communication link (or network) between two (or more) “partners”, when they are trying to talk with each other or deliver certain data between them. Jamming the communication link between a Drone and its Operator is a specific case out of many more; we can try to jam the communication between a cellular and the base station, between two tactical radios, between a bomb and a remote control that is used to activate it, etc. At the same time, it is the key equipment in electronic warfare
In order to jam, the Jammer transmits RF power (CW + Modulation) in the same frequency used by the enemy’s link or network. The enemy’s receiver (the side that “listens”) shall receive both the Jammer’s transmission and its “partner's” transmission. The stronger one shall prevail; if the drone jammer power is higher than the “partner's” power, the “listener” will not be able to “understand” correctly the message/data. Alternatively, if the “partner's” power is higher than the Jammer’s power, the “listener” will probably be able to “understand” correctly the message/data, and the communication link between the “partners” shall continue uninterrupted.
Sometimes the jamming signal arriving at the receiver input, can be lower than the communication (“partner’s”) signal and still prevail. This is happening because usually the receiver needs a certain “margin” between the two signals at its input, in order to be able to interpret one of them (usually the stronger one). However, in advanced communication systems, this “margin” can sometimes be even negative (meaning that the communication signal can be much lower than the jamming signal), and the receiver will still be able to interpret the “partner’s” signal, making jamming a much harder task.
Usually, in the Anti-Drone application, the intention is to jam the Drone when it is hundreds of meters away from the sensitive area/perimeter (where the Jammer is installed). For example, we want to jam a Drone, which is 300 meters away from the Jammer and flying at an altitude of 10 meters. As can be understood, in this case the diagonal distance between the Jammer and the Drone is about the same as the horizontal distance between them. Therefore, in order to simplify things, we will be discussing horizontal distances and we will not bother our selves with calculating the exact distance, because the difference is quite small.
This equation, though in its simplest form (without cable losses, SNR, etc.), can be used for the calculation of ANY jamming scenario/budget. As can be seen, it consists of two dimensions/links (Jammer<->Drone and Operator<->Drone), and not only one dimension/link as in the case of a communication link. In other words, for each specific condition of the Operator<->Drone link (specificoutput power, antennas gain and heights, distance, etc.), exists a specificscenario/condition of the Jammer<->Drone link, required in order to jam It… that is why answering the question of “What is the range of your Drone Jammer?” is never an easy task. There are MANY possible answers to it !