Dr Divya Chaturvedi, Assistant Professor, from the Department of Electronics and Communication Engineering has been keenly pursuing research on wearable antennas that are used within the context of Wireless Body Area Networks. These antennas are commonly used in wearable wireless communication and bio-medical RF systems. Her latest publication “Design and Investigation of Dual-Band 2×2 Elements MIMO Antenna-Diplexer Based on Half-mode SIW” was featured in the Q1 journal, IEEE Access, having an Impact Factor of 3.37. The research was done in collaboration with Assistant Professor Dr Goutam Rana and Research Scholar Ms Buela Pramodini from the Department of Electronics and Communication Engineering.
This antenna is designed to enhance data rate twice as much as a single antenna. The antenna can be used to operate in two frequency bands simultaneously, without causing any interference. One frequency band can be used for the transmission of data while the other frequency band can be utilised for the reception of data. The radiating elements are configured in such a way that it occupies a compact size. Thus, the designed antenna can be easily mounted or integrated into a portable wireless electronic device. The field from one radiating element is not coupled to the other element due to their adequate isolation that mitigates the interference problem.
The dual-band self-diplexing 4-port MIMO antenna operates in the lower frequency band around 3.4 GHz (3.35-3.55 GHz, 160 MHz) for the TD-LTE system and in the higher frequency band around 4.2 GHz (4.14-4.34 GHz, 200 MHz) for FCC ID WLAN in 5G LTE communication. The electronic devices which operate in these frequency bands can enhance the data transmission and reception speed twice as much as a single element. In other words, the proposed design prototype also improves the reliability of communication by employing the spatial multiplexing technique. In future, they plan to work on the design and investigation of MIMO-based self-diplexing antenna using the polarization diversity technique.
Abstract of the Research
In this article, a compact dual-band, 2-elements antenna-diplexer is investigated and extended to a 2×2 multi-input and multi-output (MIMO) antenna. The proposed design employs half-mode Substrate Integrated Waveguide (HMSIW) technology, which reduces the antenna footprint by 50%. To enhance the bandwidth, a rectangular slot is engraved at the center of each HMSIW cavity. The slot splits the dominant mode of the HM cavity into two odd- and even-half TE110 modes in proximity, which leads to enhancement in the bandwidth by 50%. The antenna resonates around 3.4 GHz with a fractional bandwidth of 5% and around 4.3 GHz with a bandwidth of 4.7%, when corresponding ports are excited, respectively. Both the lower and upper frequency bands can be tuned individually, by simply altering the dimensions of each HMSIW cavity. This can be achieved in a common antenna, without employing filters, which satisfies the antenna-diplexer function. The isolation levels between any two radiating elements are obtained below -23 dB for the proposed MIMO antenna, and it occupies an overall size of 1.0λg × 0.8λg. The peak gain of the antenna is obtained at 5.35 dBi in the lower frequency band and at 6.75 dBi in the upper frequency band while radiation efficiency is better than 80% in both frequency bands.