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Tumor-free status at repeat transurethral bladder tumor resection improves the bacillus Calmette-Guerin response rate and delays tumor recurrence. During followup recurrence in residual tumor-free patients develop more likely as low grade lesions than in patients with residual tumor at repeat transurethral bladder tumor resection.

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Massive MIMO (MaMIMO) is a technology of primary interest for sub-6 GHz operation in the next generation cellular systems. While MaMIMO is most often linked to macrocell scenarios, where a single cell serves many users distributed over a large area, network densification will also result in scenarios where many users are served by a MaMIMO base station (BS) that is nearby. A key question is how to scale up MaMIMO: should we add more antennas to a given cell, or create multiple smaller and distributed cells that can cooperate? This paper documents the measured performance of a very dense MaMIMO system for an indoor-to-outdoor propagation environment. The impact of the number of antennas, and the distribution of the antenna elements is experimentally verified for a simplified linear deployment of the BSs. Concretely, we serve 12 closely located users with 16, 32 or 64 antennas. We compare a centrally positioned collocated array and two distributed arrays with their uplink throughput in a licensed 2.6 GHz band. The experimental results show that 12 users can be served with only 32 antennas for the distributed topology, which is effectively only 16 antennas per MaMIMO BS. For the specific case analyzed in our measurement campaign, with the centralized deployment, 64 antennas are needed to obtain good performance, while distributing the antenna elements in two sub-arrays improves total performance and fairness between the users.

To obtain Tx-Rx isolation in an in-band full-duplex (IBFD) transceiver, the electrical-balance duplexer (EBD) can be utilized to suppress the self-interference (SI). Although the EBD can provide more than 50 dB cancellation of the SI directly at RF, it cannot fully overcome strong signals reflecting off of nearby objects. As a result, the environmental reflections could still limit the performance of IBFD communication and have to be attenuated in an extra cancellation step, e.g. in digital baseband using a digital SI canceler. While mitigating the reflections is a challenging dimension of this technology, it opens a new opportunity to perform environmental sensing. In this paper, an IBFD transceiver architecture is introduced to enable such context-aware communication functionality. We investigate how the EBD's SI rejection property influences the performance of the proposed communication device which also functions as a Doppler radar. The simulation result demonstrates that the proposed architecture can produce high-resolution Doppler when the EBD provides > 20 dB Tx-Rx isolation. Concerning the constraints dictated by the application, this paper finally suggests a radar-communication trade-off.Index Terms-In-band full duplex, self-interference cancellation, Doppler radar, wireless sensing.

Massive MIMO promises unprecedented spectral efficiency as values exceeding 140 b/s/Hz have already been demonstrated in the lab for a single cell. In this paper, based on measurements obtained in a distributed Massive MIMO testbed, we compare the spectral efficiency, area spectral efficiency, and capacity of two adjacent cells under different levels of cooperation and the impact of co-channel interference. This is the first Massive MIMO measurement based analysis of the performance of spectrum and infrastructure sharing, showing that in fully cooperative systems (sharing infrastructure and spectrum) there is an improvement of the area spectral efficiency by 50% and a sixfold of capacity in comparison with a scenario without sharing, i.e. conventional two-cells planning. In comparison to the scenario where only spectrum is shared, the infrastructure and spectrum sharing case also increases the area spectral efficiency by two and the overall capacity by four. In addition, the use of M-MMSE increases the performance of the system in 43% in relation to RZF, for this particular scenario when co-channel interference is considered.

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In this work, an indoor ultra-dense massive MIMO experiment is analysed to quantify the interference power that affects undesired users or victims when MR precoding is applied. To compare scenarios resulting in different favourable propagation conditions between users, the antennas are deployed as a Uniform Rectangular Array (URA), a Uniform Linear Array (ULA) and a Distributed Uniform Linear Array (D-ULA). We study scenarios where multiple users are served simultaneously. At the same time, the ultra-dense set of possible user locations is sub-sampled on a grid with a variable distance between users ranging from 50mm to 600mm. This work shows, on the one hand, that a URA antenna configuration provides the highest power to victim users and the worst power distribution towards target users. On the other hand, due to improved favourable propagation conditions for many user location pairs, the D-ULA topology reduces the power to victim users. Moreover, it guarantees that the power received by the target user will always be at least 3dB higher than any other victim user even if the users are closer as 100mm, for our analysis based on an indoor data-set and up to three target users.