Wideband RF Interference Reduction Module

Sanggee Kang,Heonjin Hong,Youngjun Chong 한국인터넷방송통신학회 2022 Journal of Advanced Smart Convergence Vol.11 No.3

Interference always exists between wireless communication systems used in the same frequency band or adjacent frequency bands. In order to deploy a new wireless communication system such as a 5G system, a new frequency band must be allocated to the system. For this purpose, after analyzing interference between the existing system and the new system, a method of setting a frequency guard band or a minimum separation distance has been used as a passive method to limit the interference effect. This paper presents a wideband RF IRM(Interference Reduction Module) that can actively reduce the influence of interference between wireless communication systems. The wideband RF IRM can reduce the interference effects of 5G signals on satellite signals. The principle and structure of the wideband RF IRM are presented. The wideband RF IRM can suppress approximately 20dB of interference signal in 100MHz bandwidth when only interference signal exists. It also shows that when a 5G interference signal of -45dBm/100MHz and a satellite signal of -55dBm/40MHz exist simultaneously at a center frequency of 3.83GHz, about 15dB of 5G interference signal can be reduced in the frequency range covered by the satellite signal. The experimental results demonstrate that the wideband RF IRM can actively reduce the 5G interference signal on the satellite signal and can be used for the purpose of reducing the interference effect in a similar environment.

Characteristics of AM and PM Signals in Multi-Carrier Polar Transmitter

Sanggee Kang 한국인터넷방송통신학회 2021 Journal of Advanced Smart Convergence Vol.10 No.4

Polar transmitter can support multi-band and multi-mode operation. The efficiency of frequency usage can be increased if polar transmitters can transmit multi-carrier signals. In this paper the configuration of polar transmitters is investigated to generate multi-carrier signals. Spectrum and CCDF Simulation results of twocarrier signals generated by the polar transmitter can be used to design of PM and AM path in a polar transmitter.

Useful Characteristics for Controlling the Cancellation Performance and Center Frequency of a Linearization Loop

Sanggee Kang,Sungyong Hong 한국전자통신연구원 2006 ETRI Journal Vol.28 No.2

The cancellation performance of a linearization loop is limited by the degree of an amplitude imbalance and a phase imbalance. A delay mismatch causes a phase variation as a function of frequency. Therefore, the cancellation performance and linearization bandwidth are limited by a delay mismatch. The expression for the effects of an amplitude imbalance, a phase imbalance, and a delay mismatch on the characteristics of a linearization loop is derived and analyzed. The simulation results are compared with the results obtained by means of using a commercial simulation tool and the exact agreement is reported. The derived equation could be used in designing a linearization loop and predicting the cancellation performance of the linearization loop usefully. Some useful characteristics, known from the simulation results obtained by using the derived equation, of a linearization loop for designing and implementing feedforward amplifiers are described in detail.

Characteristics of AM and PM Signals in Multi-Carrier Polar Transmitter

Kang, Sanggee The Institute of Internet 2021 International journal of advanced smart convergenc Vol.10 No.4

Polar transmitter can support multi-band and multi-mode operation. The efficiency of frequency usage can be increased if polar transmitters can transmit multi-carrier signals. In this paper the configuration of polar transmitters is investigated to generate multi-carrier signals. Spectrum and CCDF Simulation results of two-carrier signals generated by the polar transmitter can be used to design of PM and AM path in a polar transmitter.

동일대역 간섭저감기의 설계 및 구현

강상기(Sanggee Kang),홍헌진(Heonjin Hong),정영준(Youngjun Chong) 한국전기전자학회 2020 전기전자학회논문지 Vol.24 No.4

기존의 동일대역 간섭저감 방법은 무선기기 사이에 물리적인 이격거리를 지정하는 것으로 이격거리를 통해서 간섭을 억제한다. 만약 무선기기에서 동일대역 간섭을 저감할 수 있다면 물리적인 이격거리에 마진을 줄 수 있고, 수신기의 동작영역을 확장시키는 효과가 있으므로 간섭 대응 및 개선에 활용도가 크다. 본 논문에서는 동일대역 아날로그 간섭저감기의 구조를 제안하였고, 제안한 아날로그 간섭저감기의 설계와 구현에 대해서 기술하였다. 아날로그 간섭저감기를 설계하기 위해서 아날로그 간섭저감기의 성능에 영향을 미치는 지연(delay) 불일치, 위상오차 그리고 지연선로의 수에 따른 간섭저감 성능을 시뮬레이션 하였다. 16개의 지연선로로 구성된 아날로그 간섭저감기를 제작하였으며, 구현한 간섭저감기는 3.32㎓의 중심주파수에서 40㎒ 대역폭을 갖는 5G(NR-FR1-TM-1.1) 신호에 대해서 약 10dB의 간섭저감 성능을 갖는다. 본 논문에서 제안한 아날로그 간섭저감기는 동일대역 간섭저감기로 활용가능하다. The existing in-band interference reduction method recommends the physical separation distance between wireless devices and interference signals, and the interference can be suppressed through the separation distance. If the in-band interference signals can be reduced in a wireless device, a margin can be given to the physical separation distance. Since there is an effect of extending the receiver dynamic range of receivers, it is highly useful for interference reduction and improvement method. In this paper, the structure of an in-band analog IRM(Interference Reduction Module) is proposed and the design and implementation of the proposed analog IRM are described. To design an analog IRM, the interference reduction performance according to the delay mismatch, phase error and the number of delay lines that affect the performance of the analog IRM was simulated. The proposed analog IRM composed of 16 delay lines was implemented and the implemented IRM has the interference reduction performance of about 10㏈ for a 5G(NR-FR1-TM-1.1) signal having a 40㎒ bandwidth at a center frequency of 3.32㎓. The analog IRM proposed in this paper can be used as an in-band interference canceller.

버틀러 매트릭스의 설계 및 구현

강상기(Sanggee Kang) 한국통신학회 2014 韓國通信學會論文誌 Vol.39 No.9(통신이론)

TVWS용 광대역 고선형 전력증폭기

강상기(Sanggee Kang) 한국통신학회 2014 韓國通信學會論文誌 Vol.39 No.10(통신이론)

주파수 가변 캐비티 대역통과필터의 설계 및 구현

강상기(Sanggee Kang) 한국정보전자통신기술학회 2020 한국정보전자통신기술학회논문지 Vol.13 No.6

최근에는 수요자의 다양한 요구를 충족하는 서비스를 제공하기 위해서 여러 개의 무선통신 시스템을 하나로 통합한 무선기기에 대한 수요가 증가하고 있다. 다양한 무선통신 시스템으로 구성된 무선기기에는 많은 주파수 고정형 필터가 필요하다. 주파수 가변 필터는 다수의 주파수 고정형 필터를 대체할 수 있으며, 주파수 가변 필터를 사용하면 시스템을 보다 효율적으로 구성할 수 있다. 본 논문에서는 800 ~ 2400MHz 대역에서 동작하는 3-폴 주파수 가변 대역통과필터(BPF)를 설계하였다. 주파수 가변범위를 넓히기 위해서 튜닝 스크류는 스텝을 갖도록 설계하였고, 튜닝 스크류의 조절을 용이하게 하기 위해서 리니어 모터를 사용하였다. 구현한 주파수 가변 BPF는 설계한 주파수 범위에서 동작하며, 삽입 손실은 최대 2.82dB, 중심주파수에서 ± 50MHz 이격된 지점에서 최소 18.7dB의 감쇠 성능을 갖는다. In recent years, the demand for wireless devices incorporating several wireless communication systems into one has been increasing in order to provide services that meet the diverse needs of consumers. Wireless devices consisting of various wireless communication systems require many frequency fixed filters. A frequency tunable filter can replace a number of frequency fixed filters in the wireless devices. If a frequency tunable filter is used in wireless systems, the system can be configured more efficiently. In this paper, a 3-pole frequency tunable BPF(bandpass filter) operating in the frequency band of 800 ~ 2400MHz is designed. In order to widen the operating frequency band, a tuning screw is designed to have a step and a linear motor is used to facilitate the adjustment of the tuning screw. The implemented frequency tunable BPF operates in the designed frequency range and has the maximum insertion loss of 2.82dB in the channel band and the minimum attenuation of 18.7dB at ± 50MHz frequency offset from the center frequency of the band.

S-밴드용 간섭저감기

강상기(Sanggee Kang),홍헌진(Heonjin Hong),정영준(Youngjun Chong) 한국통신학회 2022 韓國通信學會論文誌 Vol.47 No.2

IRM(Interference Reduction Module) that can improve frequency utilization efficiency is designed and implemented. IRM has the interference reduction performance of above 20dB in a 100MHz bandwidth when only an interference signal exists at the center frequency of 3.77GHz. When a part of the frequency band occupied by the interference signal and the interfered signal overlaps, IRM has an interference reduction performance of above 10dB in the frequency band with only the interference signal and 5dB of interference reduction performance in the band where there are two signals.

광대역전력분배기의 설계 및 제작

강상기(Sanggee Kang) 한국통신학회 2014 韓國通信學會論文誌 Vol.39 No.9(통신이론)