 ORTHOGONAL CONVOLUTIONAL UNCODED, OPTIMUM DIVERSITY DUAL - 3, RATE 1/3 CONVOLUTIONAL (7, 1/3) 8-ARY CONVOLUTION- AL CODE Eb/NJ , dB Figure 2.69. Same as previous figures with K = 4. The dual-4, rate 1/2 convolutional code performance is almost as poor as orthogonal convolutional coding. The dual- 4, rate 1/3 performance is marginally better than optimum diversity (e.g., about 1 dB better at P = 10-5). Coding Countermeasures WC PARTIAL-BAND NOISE UNCODED, OPTIMUM DIVERSITY ORTHOGONAL CONVOLUTIONAL CODE DUAL -5, RATE 1/2 CONVOLUTIONAL CODE DUAL - 5, RATE 1/3 CONVOLUTIONAL CODE Eb/N, dB Figure 2.70. Same as previous figures, except K = 5. The 32-ary orthogonal con- volutional code is now better than the dual-5, rate 1/2 code, although both codes per- form poorly at low Pb's. The dual-5, rate 1/3 code is again about 1 dB better than optimum diversity at P = 10-5. WC PARTIAL-BAND NOISE UNCODED, OPTIMUM DIVERSITY ORTHOGONAL CONVOLUTIONAL CODE DUAL -5, RATE 1/2 CONVOLUTIONAL CODE DUAL - 5, RATE 1/3 CONVOLUTIONAL CODE Eb/Nj, dB Figure 2.71. Same as Figure 2.66, but for worst case n = 1 band multitone jamming. Remember that this entire series of graphs is for the soft decision energy detection metric with linear combining and perfect side information. Odenwalder's codes again provide the best performance, with a 1.5 dB improvement over the noise jamming case at Pb = 10-5. Some of the curves are truncated because G(D) is invalid for small EIN Non-Coherent Frequency-Hopped Systems WC n= I BAND MULTITONE ORTHOGONAL CONVOLUTIONAL CODE UNCODED, OPTIMUM DIVERSITY DUAL - 2, RATE 1/2 CONVOLUTIONAL CODE DUAL-2, RATE 1/3 CONVOLUTIONAL (7, 1/2) 4-ARY CONVOLUTIONAL CODE Eb/N,,BB Figure 2.72. Same as Figure 2.67 for multitone jamming. The orthogonal convolu- tional codes continue to be vulnerable to worst case jamming. Trumpis' (7,1) code is about 3.5 dB better than optimum diversity as in the noise jamming case, but the multi- tone jammer degrades its performance about .75 dB relative to the noise jammer. WC n= I BAND MULTITONE ORTH