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234 Linear Amplifier Design Tools
Table 7.2.
RO
(DetM)-'
Register Assignments and Address Sequences for Bilinear Coefficient
Program A7-\
RI
z,
R2
R3
z,
R4
W,
R5
z)
R6
W)
R7 R8" R9
D" D" D 12
a, a, a)
For DetM
For aJ
Register C
56 8 34 8 I 0
56834827'
For a,: 6 4 I 9, 2 6 3 9, and 4 2 5 9
For a,: 34 9 8 7 3 8 4 8
Register D
12856830
12 8 56 8 4 7'
Register E
34812850
34 8 12 8 6 7'
QR8 used for scratch during det M and a l
calculations.
b Add digits I 7 by +0.o00ooo17.
register assignments and sequences in Table 7.2. For example, consider the a3
computation from (7.14) according to the register address sequence shown in
Table 7.2. Register 6 (the primary and secondary pair) contains complex w 3
'
and register 4, containing w z , is subtracted from that; the result is multiplied
by Z, from register I, and this is summed into the register-9 pair. Digit pairs
are required when incorporating the P; values defined in (7.8). The az calculation
according to (7.7) requires the sequence shown in Table 7.2; there,
P,=Z,wz from registers 3 and 4, and this is multiplied by a 3 from register 9,
and so on. Table 7.3 contains a consistent set of data to test program
operation.
There are also means for determining the bilinear coefficients in (7.1) when
the (Z;, w;) data are noisy and i>3, as occurs for measured data pairs. In this
case, the data pairs require weighting. Suppose that one measured w value is a
moderately large impedance and another is a very small impedance. If the
measurement error is related in any fixed way to ohms, then the latter value is
much less reliable than the former. Kajfez has developed a reasonable weighting
scheme in light of the bilinear functions involved. His computation can be
Table 7.3. A Set of Bilinear Function Coefficient Data for Program A7-1
z; Wi Pi a;
I
2
3
0.1 /30 0
0.5 /60 0
l.l /-w
0.1732 /-7.8675 0
0.4473 /129.505 0
0.5099 / - 30.324"
0.0173 /22.1325 0
0.6 /75 0
0.5609 / - 40.324 0 1.4 /130"
0.2237 /189.505 0 0.18 /_23 0
D 12 =0.2406 /10.4056 0 ,
D 31 =0.5531 /-41.9136 0 ,
D23~0.7256 /153.3009 0
det M ~0.4627 /10.4030 0