The effects of harmonic distortion are generally benign, provided the total measured distortion is less than 0.01%. For multi-channel applications such as those on Broadway (i.e., 30-plus channels), the intermodulation products can increase significantly and the calculation of intermodulation-free frequencies can be done by special software. 4th-order intermodulation products (IM4): 3 x f1 - f2, 3 x f2 - f1, 3 x f1 + f2, 3 x f2 + f1 5th-order intermodulation products (IM5): 3 x f1 - 2 x f2, 3 x f2 - 2 x f1, 3 x f1 + 2 x f2, 3 x f2 + 2 x f1. The "order" of the product is the sum of the harmonic values for each of the transmit frequencies. Intermodulation Intermodulation is caused when 2 or more RF carriers are mixed in an active system and form unwanted ... 4th Order 2f 301 MHz 302 MHz 2 +f 1 2f 1 +f 2 2f 99 MHz 102 MHz 2-f 1 2f 1-f 2 3rd Order f 201 MHz 1 MHz 2 +f 1 f 1 +f 2 2nd Order f 100 MHz 101 MHz 2 f 1 1st Order The intermodulation products will cause the receiver to demodulate the wrong signal causing lots of audio issues. For example, an intermod product generated from the second harmonic of transmitter frequency A and the fundamental frequencies of B and C (2xA + B + C) is a fourth order product (2+1+1). Least Significant Bit (LSB) In a binary number, the LSB is the least weighted bit in the group. Fourth Order: 4Fl, 4F2, 2Fl+2F2, 2F2+2Fl Fifth Order: 5Fl, 5F2, 3Fl+2F2, 3F2+2Fl Additional higher orders…. Least Significant Bit (LSB) In a binary number, the LSB is the least weighted bit in the group. Of the twenty IM products listed in the table above, only the four shown in red fall close enough to the carrier frequencies to potentially cause IMD. Consequence of order There are many different intermod distortion products that occur, the main to focus on being 2nd-order, 3rd-order and 5th-order distortion products. has order |2| + |1| = 3, therefore resulting in a third-order intermodulation product. Typically, the LSB is the furthest right Secondly, the power of an IM product decreases as the order number rises. Equation 5 shows that there are several orders of intermodulation products: first, second-order products, then third-order, fourth-order, fifth-order products, etc. Second-order products are of two categories: second-order sum products of the form f i + f j and 2f i and second-order subtract products of the form f i … In some cases it can be greater without becoming audible, but anything over 0.5% is decidedly 'lo-fi' (as opposed to 'hi-fi'). Intermodulation Effects. As you can see, the remaining two equations in the fourth column result in f P of orders |1| + |3| = 4 and |2| + |3| = 5, respectively. Based on IMD products which are generated there will be second order, third order, fourth order and so on. The frequencies which are generated due to intermodulation can be sum or difference of various IMD products. of Passive Intermodulation and Distance-To-PIM. In each equation of the third column, f P has order |2| + |2| = 4, making each a fourth-order product. Typically, the LSB is the furthest right bit. In other words, 2nd order IM products contain more power than 3rd order, which contain more power than 4th order, and so on. 4th-order intermodulation products (IM4): 3 x f1 - f2, 3 x f2 - f1, 3 x f1 + f2, 3 x f2 + f1 5th-order intermodulation products (IM5): 3 x f1 - 2 x f2, 3 x f2 - 2 x f1, 3 x f1 + 2 x f2, 3 x f2 + 2 x f1. Product Order. 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