Showing papers on "Channel allocation schemes published in 1982"
TL;DR: In this article, a time and frequency division multiple access (TD/FDMA) scheme, which is a combination scheme of TDMA and FDMA, is proposed as one of the possible solutions for the problems of setting up a large number of base station transceivers and realizing a low-cost highly stabilized local oscillator.
Abstract: Multiple access is an indispensable technique for efficient radio spectrum utilization in mobile radio systems, because a large number of subscribers can be connected only when they require radio channels. Frequency division multiple access (FDMA) scheme using single channel per carrier (SCPC) has been widely used. However, the SCPC-FDMA scheme has some problems, such as difficulty in setting up a large number of base station transceivers and in realizing a low-cost highly stabilized local oscillator. A time and frequency division multiple access (TD/FDMA) scheme, which is a combination scheme of TDMA and FDMA, is proposed as one of the possible solutions for these problems. After explaining the background of the proposal, some of the restrictions of the TD/FDMA scheme resulting from the land mobile radio channel characteristics are described. Basic concept of the digital mobile radio telephone system using TD/ FDMA scheme is then presented. An example of the possible system design is finally shown.
27 citations
Proceedings Article•
01 Jan 1982TL;DR: In this paper, the authors compared several satellite uplink and downlink accessing schemes for a customer premises service (CPS) in the 30/20 GHz band, and showed that the system capacity is limited by the available satellite resources and by the terminal size and cost.
Abstract: This study compares several satellite uplink and downlink accessing schemes for a Customer Premises Service Four conceptual system designs are presented: Satellite-Routed FDMA, Frequency-Routed TDMA, Satellite-Switched TDMA, and Processor-Routed TDMA, operating in the 30/20 GHz band The designs are compared on the basis of estimated satellite weight, power consumption, and cost The system capacities are analyzed for a fixed multibeam coverage of CONUS Analysis shows that the system capacity is limited by the available satellite resources and by the terminal size and cost
2 citations
Patent•
20 Dec 1982
TL;DR: In this paper, the authors propose to simplify the method of exchange, and to make a device small-sized and light in weight, by commonly using transmission and reception frequencies for channel allocation in all terminal staions and connecting a channel with an arbitrary objective terminal station.
Abstract: PURPOSE:To simplify the method of exchange, and to make a device small-sized and light in weight, by commonly using transmission and reception frequencies for channel allocation in all terminal staions and connecting a channel with an arbitrary objective terminal station. CONSTITUTION:A frequency f0 is assigned to a common control channel 31 of a satellite 10 and frequencies fa-ff are assigned to the transmission of each earth station 1-6. When a call takes place, calling information is transmitted by using the channel 31 in frequency f0. All the stations 1-6 always receive the channel 31 and a called station receiving the calling information through the channel 31 transmits a confirming signal which informs the reception of the calling information by using the channels in the frequencies fa-ff. A calling station receiving the confirmation signal through the channels of fa-ff uses a frequency corresponding to the station number and starts communication. Thus, the common control channel is used for the calling station only, allowing to decrease and simplify the communication device for the common control channel, and the common use between the communication device for the control channel and the communication device can be attained.
1 citations