Opportunistic Communication (Cognitive Radio) over Primary Discarded Subchannels by Applying a Double Power Distribution

<table>System’s performance comparison (128/2048 subchannels, <svg height="15.425" id="M48" style="vertical-align:-3.4098pt" version="1.1" viewbox="0 0 27.012501 15.425" width="27.012501" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,11.112)"><path d="M619 482q0 -69 -40.5 -119t-96 -72.5t-118.5 -26.5h-44l-70 20l-31 -151q-14 -67 0.5 -83t89.5 -22l-5 -28h-287l8 28q65 7 81.5 22t29.5 83l79 398q12 56 0.5 70.5t-78.5 20.5l7 28h255q108 0 164 -43t56 -125zM524 478q0 141 -146 141q-25 0 -47 -8q-16 -6 -20.5 -13.5
t-10.5 -39.5l-43 -241q37 -13 83 -13q67 0 125.5 45t58.5 129z" id="x1D443"></path></g>
<g transform="matrix(.012,-0,0,-.012,10.875,15.187)"><path d="M46 650h247q112 0 169 -41q64 -49 64 -141q0 -91 -56.5 -143t-138.5 -62q-23 -3 -45 -1l-74 19v-157q0 -63 15.5 -77t83.5 -19v-28h-271v28q60 5 74 20t14 77v400q0 65 -12.5 79t-69.5 18v28zM212 559v-245q31 -12 73 -12q59 0 102 38t43 124q0 77 -42.5 115.5
t-108.5 38.5q-44 0 -56 -12q-11 -8 -11 -47z" id="x50"></path></g><g transform="matrix(.012,-0,0,-.012,17.574,15.187)"><path d="M716 650v-28q-46 -3 -65 -15.5t-22 -43.5q-6 -54 -6 -162v-82q0 -184 -75 -264q-68 -69 -180 -69q-98 0 -160 48q-88 67 -88 238v249q0 66 -13.5 81t-73.5 20v28h258v-28q-59 -4 -72.5 -19t-13.5 -82v-227q0 -122 48 -188t140 -66q189 0 189 286v75q0 111 -7 165
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</svg> = 80% &amp; <svg height="15.4375" id="M49" style="vertical-align:-3.41936pt" version="1.1" viewbox="0 0 25.737499 15.4375" width="25.737499" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,11.112)"><path d="M619 482q0 -69 -40.5 -119t-96 -72.5t-118.5 -26.5h-44l-70 20l-31 -151q-14 -67 0.5 -83t89.5 -22l-5 -28h-287l8 28q65 7 81.5 22t29.5 83l79 398q12 56 0.5 70.5t-78.5 20.5l7 28h255q108 0 164 -43t56 -125zM524 478q0 141 -146 141q-25 0 -47 -8q-16 -6 -20.5 -13.5
t-10.5 -39.5l-43 -241q37 -13 83 -13q67 0 125.5 45t58.5 129z" id="x1D443"></path></g>
<g transform="matrix(.012,-0,0,-.012,10.875,15.187)"><path d="M409 504l-29 -5q-16 60 -44.5 96t-86.5 36q-54 0 -82.5 -32t-28.5 -77q0 -51 30.5 -82.5t96.5 -65.5l35.5 -18t33 -19.5t33.5 -23.5l27 -25.5t24.5 -32t13.5 -36.5t6 -45q0 -80 -62 -134.5t-160 -54.5q-47 0 -98 15q-22 7 -50 21q-8 23 -27 155l30 7q7 -27 18 -52
t30 -51.5t49 -42.5t67 -16q56 0 88 32.5t32 87.5q0 51 -31.5 82t-98.5 67q-80 44 -110 73q-55 53 -55 124q0 75 56 126.5t150 51.5q53 0 126 -23z" id="x53"></path></g><g transform="matrix(.012,-0,0,-.012,16.301,15.187)"><path d="M716 650v-28q-46 -3 -65 -15.5t-22 -43.5q-6 -54 -6 -162v-82q0 -184 -75 -264q-68 -69 -180 -69q-98 0 -160 48q-88 67 -88 238v249q0 66 -13.5 81t-73.5 20v28h258v-28q-59 -4 -72.5 -19t-13.5 -82v-227q0 -122 48 -188t140 -66q189 0 189 286v75q0 111 -7 165
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</svg> = 20%), SNR = 8 dB, 16 dB, and 24 dB.</table>

International Journal of Digital Multimedia Broadcasting

fig9

Figure 9

Figure 9: Opportunistic Communication (Cognitive Radio) over Primary Discarded Subchannels by Applying a Double Power Distribution 