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In this paper we investigate the temperature dependent behavior of a liquid crystal (LC) loaded tunable dielectric image guide (DIG) phase shifter at millimeter-wave frequencies from 80 <inline-formula><math display="inline"><semantics><mi mathvariant="normal">G</mi></semantics></math></inline-formula><inline-formula><math display="inline"><semantics><mi>Hz</mi></semantics></math></inline-formula> to 110 <inline-formula><math display="inline"><semantics><mi mathvariant="normal">G</mi></semantics></math></inline-formula><inline-formula><math display="inline"><semantics><mi>Hz</mi></semantics></math></inline-formula> for future high data rate communications. The adhesive, necessary for precise fabrication, is analyzed before temperature dependent behavior of the component is shown, using the nematic LC-mixture GT7-29001. The temperature characterization is conducted by changing the temperature of the LC DIG’s ground plane between <inline-formula><math display="inline"><semantics><mrow><mo>−</mo><mn>10</mn></mrow></semantics></math></inline-formula><inline-formula><math display="inline"><semantics><mrow><msup><mrow></mrow><mo>∘</mo></msup><mi mathvariant="normal">C</mi></mrow></semantics></math></inline-formula> and 80 <inline-formula><math display="inline"><semantics><mrow><msup><mrow></mrow><mo>∘</mo></msup><mi mathvariant="normal">C</mi></mrow></semantics></math></inline-formula>. The orientation of the LC molecules, and therefore the effective macroscopic relative permittivity of the DIG, is changed by inserting the temperature setup in a fixture with rotatable magnets. Temperature independent matching can be observed, while the insertion loss gradually increases with temperature for both highest and lowest permittivity of the LC. At 80 <inline-formula><math display="inline"><semantics><mrow><msup><mrow></mrow><mo>∘</mo></msup><mi mathvariant="normal">C</mi></mrow></semantics></math></inline-formula> the insertion loss is up to <inline-formula><math display="inline"><semantics><mrow><mn>1.3</mn></mrow></semantics></math></inline-formula><inline-formula><math display="inline"><semantics><mi mathvariant="normal">d</mi></semantics></math></inline-formula><inline-formula><math display="inline"><semantics><mi mathvariant="normal">B</mi></semantics></math></inline-formula> higher and at <inline-formula><math display="inline"><semantics><mrow><mo>−</mo><mn>10</mn></mrow></semantics></math></inline-formula><inline-formula><math display="inline"><semantics><mrow><msup><mrow></mrow><mo>∘</mo></msup><mi mathvariant="normal">C</mi></mrow></semantics></math></inline-formula> it is <inline-formula><math display="inline"><semantics><mrow><mn>0.6</mn></mrow></semantics></math></inline-formula><inline-formula><math display="inline"><semantics><mi mathvariant="normal">d</mi></semantics></math></inline-formula><inline-formula><math display="inline"><semantics><mi mathvariant="normal">B</mi></semantics></math></inline-formula> lower than the insertion loss present at 20 <inline-formula><math display="inline"><semantics><mrow><msup><mrow></mrow><mo>∘</mo></msup><mi mathvariant="normal">C</mi></mrow></semantics></math></inline-formula>. In addition, the achievable differential phase is reduced with increasing temperature. The impact of molecule alignment to this reduction is shown for the phase shifter and an estimated 85% of the anisotropy is still usable with an LC DIG phase shifter when increasing the temperature from 20 <inline-formula><math display="inline"><semantics><mrow><msup><mrow></mrow><mo>∘</mo></msup><mi mathvariant="normal">C</mi></mrow></semantics></math></inline-formula> to 80 <inline-formula><math display="inline"><semantics><mrow><msup><mrow></mrow><mo>∘</mo></msup><mi mathvariant="normal">C</mi></mrow></semantics></math></inline-formula>. Higher reduction of differential phase is present at higher frequencies as the electrical length of the phase shifter increases. A maximum difference in differential phase of 72<inline-formula><math display="inline"><semantics><msup><mrow></mrow><mo>∘</mo></msup></semantics></math></inline-formula> is present at 110 <inline-formula><math display="inline"><semantics><mi mathvariant="normal">G</mi></semantics></math></inline-formula><inline-formula><math display="inline"><semantics><mi>Hz</mi></semantics></math></inline-formula>, when increasing the temperature from 20 <inline-formula><math display="inline"><semantics><mrow><msup><mrow></mrow><mo>∘</mo></msup><mi mathvariant="normal">C</mi></mrow></semantics></math></inline-formula> to 80 <inline-formula><math display="inline"><semantics><mrow><msup><mrow></mrow><mo>∘</mo></msup><mi mathvariant="normal">C</mi></mrow></semantics></math></inline-formula>. Nevertheless, a well predictable, quasi-linear behavior can be observed at the covered temperature range, highlighting the potential of LC-based dielectric components at millimeter wave frequencies.