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Showing papers by "Amitava Ghosh published in 2005"


Patent
19 Apr 2005
TL;DR: In this article, uplink rate control signaling is proposed to achieve increased sector and user throughput with relatively high uplink spectrum efficiency by using two common persistence values (404, 408) and SHO status and buffered data.
Abstract: Embodiments described herein address the desire to have a method for uplink rate control signaling that is able to achieve increased sector and user throughput with relatively high uplink spectrum efficiency. Rate control signaling embodiments are disclosed that use two common persistence values (404, 408) to update the allocated portion of RoT margin for each UE device, and thus, reduce the variation of the RoT. In addition, SHO information is used to control the inter-sector/cell interference and improve the sector throughput. In such embodiments, each UE determines (412) the data rate and time to transmit according to these common persistence values, SHO status and buffered data. Throughput comparable to that of time and rate schedulers, which require significantly more signaling and information, can be achieved by some of these embodiments while also exhibiting less sensitivity to delay, speed of the UE, and burstiness of the traffic.

45 citations


Proceedings ArticleDOI
25 Sep 2005
TL;DR: It is shown that approximately 35-40 Erlangs could be supported with a delay bound of around 250 msec for mobile-to-mobile call for HRPD-A and around 90- 100 Erlang’s for HSDPA/HSUPA combination with a similardelay bound of HR PD-A.
Abstract: Third generation wireless communication systems, such as High Rate Packet Data (HRPD-A), also known as 1xEV-DO Revision A, and High Speed Downlink/Uplink Packet Access (HSDPA/HSUPA) have been standardized to support high-speed data and Internet access in cellular systems. Advanced techniques such as adaptive modulation and coding, Hybrid ARQ (H-ARQ), fast scheduling and a de- centralized architecture have been included in these systems to achieve high peak data rate and significantly higher sector and user throughput. It is shown that approximately 35-40 Erlangs could be supported with a delay bound of around 250 msec for mobile-to-mobile call for HRPD-A and around 90- 100 Erlangs for HSDPA/HSUPA combination with a similar delay bound of HRPD-A.

13 citations


Patent
13 Dec 2005
TL;DR: In this article, a margin between a power need of a data channel of a packet and the total available transmit power of the network infrastructure device is determined, and resources are allocated responsive to the margin to further determine the subsequent packet.
Abstract: In a network, where a packet is to be transmitted on a channel to a communication device with a time offset between a shared control channel and a shared data channel, the packets can be ordered (401). A margin can be determined (403) between a power need of a data channel of a packet and a total available transmit power of the network infrastructure device. Scheduling packets (405) is responsive to the margin, and determines the next packet to be sent, where the control channel of the next packet has a power need less than the powe margin (407). Resources are allocated (409) responsive to the margin to further determine the subsequent packet. The subsequent pack is transmitted (411) on the channel, wherein the data channel of the current packet and the control channel of the subsequent packet are at least partially contemporaneous.

12 citations


Patent
09 Feb 2005
TL;DR: In this paper, a null generator is used to generate an output data symbol sequence that exhibits nulls in the frequency domain at particular frequencies that an input data signal does not, and a pilot inserter is added to this output signal to create a combined symbol sequence.
Abstract: Various embodiments are described to provide for the transmission and reception of data in an improved manner. Data transmission is improved by including in a transmitter a null generator (110) to generate an output data symbol sequence that exhibits nulls in the frequency domain at particular frequencies that an input data symbol sequence does not. A pilot inserter (120) then adds a pilot symbol sequence to this output data symbol sequence to create a combined symbol sequence. Since the pilot symbol sequence exhibits pilot signals corresponding to the nulls of the output data symbol sequence in the frequency domain, the combined symbol sequence exhibits pilots that are orthogonal to the data in the frequency domain.

11 citations


Patent
10 Nov 2005
TL;DR: In this article, an outer-loop power control for enhanced uplink communications that address some of the outstanding problems in the prior art is described. But the uplink quality indicator is not considered.
Abstract: Various embodiments are described to address the need for an apparatus and method of outer-loop power control for enhanced uplink communications that address some of the outstanding problems in the prior art. Generally expressed, a base site (131), while a first uplink channel is inactive, monitors packet retransmissions to generate an uplink quality indicator. Here, packet retransmissions refers to the number of packet retransmissions used by a remote unit (101) to send packets to a base transceiver station (111) via at least one other uplink channel. Also, while the first uplink channel is inactive, the base site adjusts a signal-to-interference ratio (SIR) target for the first uplink channel based on the uplink quality indicator. Then, when the first uplink channel becomes active, the base site begins power controlling the first uplink channel using the SIR target.

10 citations