Sanggee Kang

The characteristics of a transmitter's ACLR for WCDMA

Effects of a drivers adjacent channel leakage ratio (ACLR) on the total ACLR have been tested in order to investigate the relationship between the ACLR of a driver and a DUT. The ACLR test results show that the degradation in ACLR is 4.1-4.5 dB when the both ACLR values are the same. If the difference of ACLR values between a source and a DUT is 12-12.5 dB, then there is no degradation in total ACLR.

The implementation of a base station transceiver for WLL system based on wideband CDMA

The implementation of a BTS (base station transceiver) for a WLL system using a wideband CDMA (W-CDMA) method is presented. It consists of three boards; receiver, transmitter, and RF controller. Some RF parameters are considered and simulated by the RF simulation software using commercial and customized component specifications. The implemented transceiver of 5 MHz RF channel bandwidth satisfies the system requirements of a transceiver such as dynamic range, receiver sensitivity, and spurious emission suppression in the transmitter. At the receiver, the experimental measurement showed a noise figure (NF) of 2.86 dB and a dynamic range of above 60 dB in AGC locking. At the transmitter, the -49.34 dBc of spurious emission suppression is attained when the output power of the transmitter is 34.3 dBm. These results are good enough to meet standard performance specifications.

Balancing the probability of interference caused by different communication systems for sharing frequency

In order to use frequency spectrum efficiently, many methods for increasing the data rate and improving the signal purity of spectrum in communication systems have been studied (Haykin, S., 1994). Recently how to advance the spectrum policy for the efficient use of frequency resources in the future was investigated [2]. According to the results of the study, we can increase the efficiency of using frequency resources through the competition rather than the regulation of using frequency resources.

Technical Analysis for Flexible Access Common Spectrum(FACS)

A frequency sharing technique is necessary for using the limited frequency resources efficiently. In this paper we study the condition for sharing frequency bands in two cases. One is the case that the frequency band is already allocated to the specific communication. The other is the case of allocating the new frequency bands to communication systems having interference avoiding techniques. For each case we investigate the conditions for sharing frequency bands and the suggestions for that are presented in this paper.

Balancing the transmission characteristics for sharing frequency spectrum

A frequency sharing technique is necessary for using the limited frequency resources efficiently. In this paper we study the condition for sharing frequency bands in two cases. One is the case that the frequency band is already allocated to the specific communication. The other is the case of allocating the new frequency bands to communication systems having interference avoiding techniques. For each case we investigate the conditions for sharing frequency bands and the suggestions for that are presented in this paper.

The implementation of RTU and RSU transceiver for WLL system

The implementation of RTU and RSU transceiver for Korean WLL system based on W-CDMA is presented in this paper. RTU transceiver consists of three boards; receiver, transmitter and RF controller. RSU transceiver is divided into three parts; receiver, transmitter and IF board. At the RTU receiver, the experimental measurement shows 2.86 dB of NF and 60 dB above of dynamic range in AGC locking. At the RTU transmitter, the -49.34 dBc of ACPR is attained when the output power of the transmitter is 34.3 dBm. At the RSU receiver, the measured of the NF shows 5.65 dB. The measured ACPR of the RSU transmitter is -49.33 dBc when the transmitter operates in normal state. These results are good enough to meet standard performance specifications.

A Design And Implementation Of Rtu And Rsu Transceiver For Wll System

The implementation of radio transceiver unit(RTU) and radio subscriber unit(RSU) transceiver for Korean wireless local loop(WLL) system based on W- CDMA is presented in this paper. RTU transceiver consists of three boards; receiver, transmitter and RF controller. RSU transceiver is divided into three parts; receiver, transmitter and IF board. At the RTU receiver, the experimental measurement showed 2.86dB of NF. At the RTU transmitter, the -49.34dBc of adjacent channel power rejection(ACPR) is attained when the output power of the transmitter is 34.3dBm. At the RSU receiver, the experimental measurement shows 5.65dB of NF. The measured ACPR of the RSU transmitter is -49.33dBc when the RSU transmitter operates in normal state. These results are good enough to meet required performance speciJications.