ɪnðə dɪzˈaɪn ʌv ɹˈeɪdɪˌoʊ bɹˈɔːdkæst sˈɪstəmz, ɪspˈɛʃəli tˈɛlᵻvˌɪʒən sˈɪstəmz, ðə dɪzˈaɪɚdtʊˌʌndɪzˈaɪɚd tʃˈænəl ɹˈeɪʃɪˌoʊ dˈiː slˈæʃ jˈuː ɹˈeɪʃɪˌoʊ ɪz ɐ mˈɛʒɚɹ ʌvðə stɹˈɛŋθ ʌvðə bɹˈɔːdkæst sˈɪɡnəl fɚɹə pɚtˈɪkjʊlɚ tʃˈænəl kəmpˈɛɹd wɪððə stɹˈɛŋθ ʌv ˌʌndɪzˈaɪɚd bɹˈɔːdkæst sˈɪɡnəlz ɪnðə sˈeɪm tʃˈænəl ˈiː.dʒˈiː. fɹʌm ˈʌðɚ nˈɪɹbaɪ tɹænsmˈɪɾɪŋ stˈeɪʃənz.
In the design of radio broadcast systems, especially television systems, the desired-to-undesired channel ratio (D/U ratio) is a measure of the strength of the broadcast signal for a particular channel compared with the strength of undesired broadcast signals in the same channel (e.g. from other nearby transmitting stations).