Adaptive modulation and other extensions of the physical layer in multiple access systems
3 Assignments
0 Petitions
Accused Products
Abstract
The present invention seeks to improve data exchange in a communications system that is especially standardized according to IEEE 802.11a. For this purpose, when the transmission medium, preferably an IEEE 802.11 system with a distributed coordination function (DCF) is accessed in a decentralized manner, pilot signals are transmitted from the transmitter to the recipients using a number of transmission modes and then an allocation table regarding the transmission modes is calculated by the recipient on the basis of the pilot symbols received. The recipient transmits the allocation table to the transmitter so that the subsequent data exchange can proceed on the basis of the allocation table. In the case of centralized access, preferably an IEEE 802.11 system with a point coordination function (PCF), data exchange is improved in that the subsequent data are adaptively modulated already when the allocation table is transmitted.
-
Citations
35 Claims
-
1-17. -17. (canceled)
-
18. A method for transmitting data signals in a communication system with access organized on a distributed basis to an access medium using a plurality of transmission modes by transmitting at least one pilot signal from a transmitter to a receiver, the method comprising:
-
calculating, by the receiver, an assignment table in respect of the transmission modes using at least one pilot signal;
transmitting the assignment table from the receiver to the transmitter; and
transmitting the data signals using the transmission modes in accordance with the assignment table in a direction which is one of from the transmitter to the receiver and from the receiver to the transmitter. - View Dependent Claims (19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30)
-
-
31. A method for transmitting data signals in a communication system with centrally organized access to a transmission medium using a plurality of transmission modes by transmitting at least one pilot signal from a transmitter to a receiver, the method comprising:
-
calculating, by the receiver, an assignment table in respect of the transmission modes using the at least one pilot signal;
transmitting the assignment table from the receiver to the transmitter; and
transmitting, in accordance with the assignment table, the data signals using the transmission modes transferred in the assignment table from the receiver to the transmitter. - View Dependent Claims (32, 33, 34, 35)
-
Specification