Alexeev, N.N. Alekseev, P.N. Andreev, V. Kulevoy, T. Milyachenko, A.D. Nikolaev, V.I. Satov, Yu.A. Shumshurov, A. Zarubin, A. JACoW Publishing Geneva, Switzerland 2226-0366 978-3-95450-194-6 10.18429/JACoW-LINAC2018-TUPO011 English 346-348 TUPO011 acceleration heavy-ion emittance laser bunching Contribution to a conference proceedings 2019 2019-01 https://doi.org/10.18429/JACoW-LINAC2018-TUPO011 http://jacow.org/linac2018/papers/tupo011.pdf Heavy ion injector I-3 represents two-gap 2.5 MHz resonator with accelerating voltage 2x2 MV. It‘s used with laser ion source for acceleration of heavy ions in wide range of charge to mass ratio. As a result of modernization, injector structure will be supplemented by the second two-gap resonator, rf voltage will be increased to 3x4 MV and accelerated beam structure has to be improved by increasing accelerating frequency to 5 MHz. Design features of upgraded linac and peculiarity of beam dynamics for different types of ions are presented.