Jussi Ojala
Nokia
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Publication
Featured researches published by Jussi Ojala.
IEEE Transactions on Vehicular Technology | 2009
Mika Rinne; Markku Kuusela; Esa Tuomaala; Pasi Kinnunen; Istvan Zsolt Kovacs; Kari Pajukoski; Jussi Ojala
Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (E-UTRA) is a new technology that targets the long-term evolution (LTE) of third generation. The E-UTRA technology has recently been standardized by the Third-Generation Partnership Project (3GPP) as a set of (series_36) specifications. The standardization process is almost complete; this paper does not focus on comparing specific proposed schemes but instead aims to outline the system performance more in general. E-UTRA operates in the packet-switched domain; hence, all traffic is handled by the packet protocols. The analysis is shown for Voice over Internet Protocol (VoIP) and Best Effort (BE) data, as these are common examples of real-time and non-real-time traffic, respectively. The performance is given in the VoIP study as the number of satisfied voice users per cell and in the BE study as the cumulative probability distribution of user (or cell) throughput, which was scaled to the spectral efficiency values, given both at the mean and at the cell edge. The VoIP capacity extends beyond 350 users in downlink and 230 users in uplink, which is a considerable increase compared with the high-speed packet-access (HSPA) reference. The BE spectral efficiency meets the 3GPP targets and yields impressive gains of order 2.5-3 times the well-performing HSPA reference. This clearly exceeds the mean of 1.5 b/s/Hz/cell in downlink and 0.8 b/s/Hz/cell in uplink for a baseline antenna configuration with penetration loss of 20 dB. In some scenarios, these mean gains exceed four times the reference.
vehicular technology conference | 2008
Tero Henttonen; Kennett Aschan; Jani Puttonen; Niko Kolehmainen; Petteri Kela; Martti Moisio; Jussi Ojala
In this paper, we study VoIP capacity in UTRA Long Term Evolution downlink under different mobility conditions. Since LTE is designed to be a wide area system supporting very high mobility, VoIP capacity for different mobility conditions is an important measure for the LTE system. We show how the mobility dynamics affect the VoIP capacity, using a dynamic system simulator to model the effects of both Robust Header Compression (ROHC) and handovers. The results indicate that the effect of non-ideal ROHC to VoIP system capacity is minimal, especially when compared to the mobility effects to system capacity.
international workshop on signal processing advances in wireless communications | 2007
Mika Rinne; Kari Pajukoski; Markku Kuusela; Klaus I. Pedersen; Jussi Ojala; Esa Tuomaala; Istvan Zsolt Kovacs; Haiming Wang; Per Henrik Michaelsen; Claudio Rosa; Juergen Michael
The evolved UMTS terrestrial radio access (E-UTRA) is a new technology being standardized by the 3GPP . E-UTRA targets for a long term evolution of 3G UMTS. This paper addresses the fundamentals of the E-UTRA technology and describes especially its gain mechanisms. As the standardization work is progressing rapidly, this paper does not focus on comparing the specific proposed schemes, but instead aims at outlining the system performance more in general. As E-UTRA operates in the packet-switched domain, all traffic is handled by packet protocols. The cellular analysis is shown with the results for a voice over internet protocol (VoIP) study case and for a best effort (BE) data study case, as these are common examples of a real-time and a non-real-time traffic, respectively. The performance is given in the number of satisfied voice users per cell and in the cumulative probability distributions of user throughput, which is scalable to the spectral efficiency.
Archive | 2003
Antti Lappeteläinen; Jussi Ojala
Archive | 2009
Esa Malkamaki; Jussi Ojala
Archive | 2004
Antti Lappeteläinen; Jussi Ojala
Archive | 2008
Esa Malkamaki; Jussi Ojala; Jari Petteri Lunden
Archive | 2008
Jussi Ojala; Benoist Sebire
Archive | 2009
Jussi Ojala; Timo Erkki Lunttila
Archive | 2008
Lars E. Lindh; Esa Malkamaki; Jussi Ojala