An analysis of the effective performance of a handset diversity antenna influenced by head, hand, and shoulder effects—A proposal for a diversity antenna gain based on a signal bit‐error rate and analytical results for the PDC system

Abstract

SUMMARYAn analysis of the effective performance of a handset diversity antenna, comprising a whip antenna and a planar inverted F antenna (PIFA), has been made by introducing a new figure-of-merit, the Diversity Antenna Gain (DAG). The analysis includes the electromagnetic interaction with a human operator. The DAG can take account of all of the effects associated with effective antenna gains, unequal median values, and correlations between diversity branches, and therefore can directly indicate the system gain in a multiple radio wave environment. By using the DAG, a direct performance comparison between diversity antennas with different effective gains and correlations can be easily made from the viewpoint of particular system criteria. This comparison is difficult to make from the respective performances only. The analysis has been made on S/4-shift QPSK signals with the assumption of a PDC system with a postdetection two-branch selection combining method or a maximum ratio combining method. The analytical results indicate DAG characteristics under various incident wave propagation environments with head-toradio separation, whip length, and inclination of the radio from the vertical as variable parameters. The results demonstrate the structural and environmental requirements for designing a diversity antenna with a high effective perform-

On the Covariance Matrix and Diversity Performance Evaluation of Compact Multiport Antenna Systems

“…On the contrary, the lower average SNR regions do not show such performance improvement. Similar trends have been observed when employing other diversity techniques such as selection combining (SC) [2] and MRC [3], [6].…”

“…Covariance matrix methods are analytical-based, as they require closed-form cumulative distribution function (CDF) and probability density function (PDF) of the received signal-to-noise-ratio (SNR). They also provide one additional potential for performance evaluation via bit error rate (BER) calculations of the combined signal [3]. The stochastic electromagnetic simulation methods are Monte Carlo-based and apply when no mathematical expressions for the CDF of received SNR are available.…”

Actual Diversity Performance of a Multiband Diversity Antenna With Hand and Head Effects

“…At low frequencies, the EDG is actually negative in value, due to the 100% efficiency reference antenna performing better than the diversity prototype with user interaction. Thus, the DG appears to be an optimistic measure of diversity performance, as it promises good performance regardless of the antennas used [4]- [7], [10], [11] or the user interaction sce-nario. On the other hand, EDG tends to be overly conservative, as it compares the diversity antenna system with a non-real antenna with no user interaction.…”

“…However, the focus has been on a single frequency band using simple and common antenna designs [4]- [13]. For the case of the planar inverted F-antenna (PIFA) and the whip antenna in the 900 MHz, the diversity handset's MEG decreases in proximity of user's hand, head, and shoulder [4]- [7]. Depending on the phone/user inclinations and propagation scenario, both increase and decrease of the correlation are observed.…”

“…It can be also calculated in reference to a theoretical upperbound Rayleigh curve as in case of ideal diversity gain IDG [17]. The concept of diversity antenna gain (DAG) [7] takes a similar approach as EDG, in the sense that it facilitates an absolute performance comparison between different diversity antenna systems. However, instead of the efficiency used in EDG, the MEG of the strongest branch in the diversity system is multiplied with the apparent DG to obtain DAG.…”