That is due to the continuity of the patent. The patent uses a series of diagrams. One of which is an example of a previous circuit using 3 diodes connected head to tail in series and three transistors cascaded to produced a cubic function output. Thus a circuit already existed to perform the cubic function. However, since this circuit was 3 PN junctions deep, it would not function in the low voltage range for which the newer design was aimed. In describing this older circuit the transistors and diodes were designated with the lower numbers. The actual circuit that the patent described then used the higher numbers.
A prior art circuit 300 used to provide a cubic function to compensate for these power amplifiers is shown in FIG. 3. The circuit 300 comprises diodes D1-D3, transistors Q1-Q3, and current sources I.sub.in, I.sub.1 and I.sub.2.
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However, the circuit 300 only functions at voltages at or above approximately 3 volts. This is because the topography of the circuit requires a voltage of 3*(V.sub.be,+V.sub.ce(sat)), and the value of V.sub.be may be as high as 0.8-0.9 volts, while the value of V.sub.ce(sat) is 0.3 volts. The 3 volt limit makes the circuit unusable for many applications.
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A cubic function generator 600 according to the present invention is shown in FIGS. 4-6. The cubic function generator 600 is designed to work in high-frequency, low voltage applications. In FIG. 4, the first portion 400 of the cubic function generator 600 is shown. The first portion 400 comprises diodes D4 and D5, transistors Q4 and Q5, and current sources I.sub.c and I.sub.3.
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The second portion 500 of the cubic function generator 600 is shown in FIG. 5. The second portion 500 comprises diodes D6 and D7, transistors Q6-Q8, and current sources I.sub.par and I.sub.3.
If you want to discuss the evolved circuit and why I was fairly certain that it was only a simulation and why I suspect the evolved circuit is not up to the task of the patented circuit. I will do so only if the exchange remains without Ad Hominem. It is simple enough and polite enough just to say, "I disagree" or "I don't see your point."
Proofread, Proofread, Proofread.