Determination of the impulse response of UWB antennas using GTEM cells

Abstract

This paper deals with a measurement method to determine the absolute impulse response of ultra-wideband (UWB) antennas. At this the antenna is placed into the testing volume of a gigahertz transverse electromagnetic (GTEM) cell, augmenting the use-case of this well-known EMC measurement device. The unit consisting of cell and antenna is excited by an UWB pulse. The chief attraction is that the impulse response of the GTEM cell can be modeled by a dirac distribution within a distinct time interval, so that within this interval an approximately plane TEM wave impinges on the antenna under test without being dispersively distorted by parasitic multimode wave propagation. Hence, the impulse response of a receiving antenna can exclusively be obtained within this distinct time interval, if further constraints, like maximal antenna size or estimated impulse response length are carefully adapted to the cell's properties. In order to verify the proposed method, it is applied to a UWB cone antenna and measurement results are compared with those derived from the two antenna method, a reference measurement incorporating two equally shaped antennas, as well as from simulations.

Transient radiation properties of tapered slot antenna

“…Similar to the approach in [3], a Wiener fil frequency domain to determine the angular de transfer function for the transmit case :…”

“…EXTRACTION OF THE ANTENA IMPULSE REPONSE FROMSIMULATIONAccording to[3] the antenna impulse response for the transmit case , , relates the transmitted electrical field , , , in azimuth angle and elevation angle to the excitation signal tx at the feeding point of the antenna by:…”

Influence of the real UWB antennas on the AoA estimation based on the TDoA localization technique

“…The constant is introduced to the equation to prevent noise enhancement (s. e. g. [4]). rx_Vivaldi (t, , ) the simulation tool "CST Microwave Studio" is used.…”

“…In the first step the TDoA and the resulting AoA is calculated directly from the received signals r 1 (n) and r 2 (n) according to the description given in We expect that the estimation error of the resulting AoA is less than the error of the AoA According to [4] deconvolution, needed in the step 2 of the algorithm, can be performed as follows:…”