# How do you calculate the jamming margin?

In DSSS signals, it is also defined as the coding rate (used for spreading) divided by the data rate. Another relevant word is "jamming margin," which is described by the formula: M J is the jamming margin (in dB), whereas G P denotes the processing gain (in decibels). The processing gain is the difference between the total power of all transmitted signal components and the power of any one interference signal component. It can be calculated as 20 log 10(NP/I), where NP is the total received power and I is the power of any one interference signal.

The processing gain is used to compare the strength of received signals with interfering signals. If the ratio of signal power to interference power is very small, then there is not enough energy in the signal to overcome the noise level. This leads to a failure to decode the message. To make sure that messages can be decoded even if interferences are strong, transmitters use codes with a large processing gain. For example, binary phase shift keying (BPSK) uses only 1 bit per symbol, but its processing gain is 4. As another example, quadrature amplitude modulation (QAM) uses 2 bits per symbol, but its processing gain is 12.

The processing gain is important because it tells us how much more power we need at the receiver to keep up with other transmissions.

## What is the jamming margin?

The amount of interference (jamming) that a system can tolerate while still maintaining a set level of performance, such as maintaining a particular bit-error ratio even when the signal-to-noise ratio decreases. The larger the jamming margin, the more resistant the system will be to interference.

In communications systems, the jamming margin is the maximum allowable amount of interference from other signals or noise sources that can be tolerated by the system before its quality deteriorates too much. For example, if the system requires an error rate of 1 in 10,000 bits for correct data transmission, then it can withstand up to 1000 interfering signals or noise sources before failing.

In radar systems, the jamming margin is the maximum allowed exposure of the target to the radar signal during an average period. If the exposure exceeds this limit, the target will be obscured by interference and cannot be seen anymore. The jamming margin depends on many factors such as the type of radar system, the frequency of the radar signal, etc.

For example, a microwave radar system with an operating frequency of 5.8 GHz and a maximum power output of 25 watts could expose a target to 2500 W/m2 for 10 ms in order to meet safety regulations. This is equal to about one tenth of the safe limit for human exposure to radiation.

## How does Matlab calculate gain margin?

[Gm, Pm, Wcg, Wcp] = margin (sys) yields the absolute gain margin Gm, phase margin Pm, and frequencies Wcg and Wcp of sys. Wcg, or a-180 degree phase crossing frequency, is the frequency at which the gain margin is measured. At this frequency, the magnitude |Z(Wcg)| = 1.

The phase margin Pm is the angle that the phase makes with the x-axis measured at Wcg. It can be calculated from the following equation:

Pm = arctan|Y(Wcg)/X(Wcg)|

Where Y(Wcg) is the amplitude response at Wcg and X(Wcg) is the phase response at Wcg.

Frequencies Wcp and Wcg are the lower and upper limits of stability, respectively. If either limit is less than 0.5 times the other, then it is set to 0.5 times the other value.

For example, if Wcg < 0.5*Wcp, then Wcg = 0.5*Wcp.

Finally, the gain margin Gm is given by Gm = Zc - |Zc| where Zc is the open-loop gain at Wcg.

## What is the throughput margin?

Margin throughput is an accounting phrase related to contribution margin that is used to measure the amount of profits earned throughout the production cycle, with an emphasis on variable costs and revenue rather than fixed expenses, which fluctuate so often that any set figure is mostly arbitrary. It is calculated by taking the total contribution margin and dividing it by the number of units produced.

For example, if a company produces 10,000 units of a product that sells for \$10,000 each with a cost of \$5,000 per unit, then its margin rate is 50 percent. The margin rate is also known as the turnover ratio or sales rate. This means that for every \$100 spent on goods and services, they expect to earn back \$50 in profit.

The margin required to cover variable costs is called the break-even point margin. At this point, if sales fall, we will need to reduce our contribution margin or volume sold to ensure that we have enough left over after covering our fixed costs. If sales increase, we can expand into new markets or use more expensive materials or methods and still stay within our margin requirements.

Some industries require higher margins than others to justify their prices. For example, a luxury brand such as Gucci would need to spend considerably more on handbags than another brand such as H&M because people are willing to pay more for a good quality bag.

## Which is the simplest definition of surge margin?

The distance between the operating point and the surge line is the most basic definition of surge margin. This concept requires some extra qualifiers in order to be used as a comparison criteria for the performance of the control system. The compressor performance map is a standard tool for defining a compressor's performance. It shows the relationship between discharge pressure and flow rate, with the amount of boost delivered by the engine indicated by the position on the graph. The closer the curve is to the left, the better the compressor performs. A good compressor will have a high surge line and a short surge zone.

Surge occurs when there is not enough gas flowing through the compressor to keep it running. If this condition persists, the motor will run continuously, which is called "surging." When this happens, the compressor will use more power than normal, because it must continue to operate in order to deliver more gas to the tank. This is why surge is often referred to as "continuous surge." Continuous surge is dangerous because the compressor could be damaged by over-loading, or even destroyed if the load is too great for it to handle properly. Surge can also happen if the valve controlling the gas flow into the compressor is accidentally left open. In this case, there is too much gas entering the compressor, so some of it gets blown by the turbine instead of being compressed. This excess gas flow reduces the efficiency of the compressor and increases the fuel consumption of the engine.

##### Sandra Henley

Sandra Henley is a teacher, writer and editor. She has a degree in English and Creative Writing from Yale University and a teaching certificate from Harvard Divinity School.