ðə ɹᵻdˈuːstˈɔːɹdɚɹ ˌɛlkjˌuːdʒˈiː pɹˈɑːbləm fˈɪkstˈɔːɹdɚɹ ˌɛlkjˌuːdʒˈiː pɹˈɑːbləm ˌoʊvɚkˈʌmz ðɪs baɪ fˈɪksɪŋ ɐ pɹaɪˈɔːɹi ðə nˈʌmbɚɹ ʌv stˈeɪts ʌvðɪ ˌɛlkjˌuːdʒˈiː kəntɹˈoʊlɚ.
The reduced-order LQG problem (fixed-order LQG problem) overcomes this by fixing a priori the number of states of the LQG controller.