Can radio frequency negative? If frequency is defined as an absolute number then there can be no negative frequencies, but if it is a real number negative frequencies can exist. You do need two signals

## Can radio frequency negative?

If frequency is defined as an absolute number then there can be no negative frequencies, but if it is a real number negative frequencies can exist. You do need two signals to distinguish between positive and negative frequencies, the same as you need two numbers to define a complex number.

### Can omega be negative?

Let ω be a nonnegative parameter with units of radians/second. Then the angular function (angle vs. time) −ωt + θ, has slope −ω, which is called a negative frequency. But when the function is used as the argument of a cosine operator, the result is indistinguishable from cos(ωt − θ).

**Can you have a negative angular frequency?**

Since rotation has two directions then the angular frequency may be positive or negative. One has a positive angular frequency and the other has a negative angular frequency. These two components when represented in the angular frequency scale they appear on the opposite side around the the zero angular frequency.

**Why is FFT negative frequencies?**

The ‘negative frequencies’ derive from the way the two-sided Fourier transform (as computed by fft) is characteristically depicted. The fft function returns a vector that appears to begin at the zero frequency and extends to the sampling frequency. The actual Fourier transform therefore has negative frequencies.

## What is negative frequency in FFT?

Negative frequency is the rotation vector in the opposite direction to the positive frequency. For example it is necessary to have a real (non-comlex) signal. Then we have two vectors rotating in opposite directions.

### What is the concept of negative frequencies?

Negative frequency is an idea associated with complex exponentials. A single sine wave can be broken down into two complex exponentials (‘spinning numbers’), one with a positive exponent and one with a negative exponent. That one with the negative exponent is where you get the concept of a negative frequency.

**Can a beat frequency be negative?**

The beat frequency is the absolute value of the difference between the two frequencies. A negative frequency would not make sense. Consider three frequencies.