One of the main purposes of the project "Communication systems for operations in urban environment" is to suggest suitable communication methods for urban environment. Orthogonal frequency division multiplexing (OFDM) and multiple-input multiple-output (MIMO) are two suitable techniques for such purpose. One part of this work is to study rules of thumb in the design of important parameters of OFDM and MIMO systems. To be specific, in this work the ratio between number of pilots and available frequency tones of an OFDM system is studied. The more pilots used gives better channel information and better choice of the parameter of adaptive modulation and coding can be made. However, more pilots imply more overhead and lower spectrum utilization. We also investigate how the number of available transmission rates in an Adaptive Coding and Modulation scheme impacts communication performance and feedback requirements. It is shown that an equal spacing of available rates over the expected range of SNRs is preferable. Design rules for the selection of rates are given. Furthermore, the impact of reducing the antenna element distance of a MIMO-system is studied. The general approach is to use an antenna element distance of at least the wavelength divided by two. At the frequency of 300 MHz such distances is functional for vehicles. However, for handheld equipment it can be troublesome. Hence, it is of interest to study the consequence of less element distance. The impairment is studied in terms of reduced capacity. This is studied for a suburban area in Linköping for a 4x4 (four transmit antennas and four receive antennas) and 2x2 antenna constellation. It is shown that the degradation is graceful as the distance decreases. For example, for a 2x2 system, the penalty of using the radius 0.125 is only about 10 % compared to the capacity if a radius of 0.25 m is used. For these results, it is assumed that the mutual coupling between the antenna elements is taken care of by other techniques and is therefore not treated in this work