Scenario card: urban-grid-10ghz¶
Dense small cells in the TR 37.885 urban grid at 10 GHz
Available since version 0.2.0. Use it as scenario: urban-grid-10ghz in a configuration file or hl.builtin_scenario("urban-grid-10ghz") in Python.
Purpose¶
The main scenario of HandoverLab and its default values: the minimum 3 x 3-block area of the TR 37.885 urban grid with small cells every 100 m along the streets, a 10 GHz carrier with the TR 38.901 UMi street-canyon model, line of sight from the building geometry plus the spatially consistent LOS state, and shadowing tied to place, so that every user passing a spot sees the same blockage. 40 vehicular users at about 60 km/h, 120 s with 20 s warm-up. Use it to compare handover rules where blockage repeats by place.
Layout¶
Three by three blocks (433 m x 250 m between street centre lines, 20 m streets), 76 sites.
Parameters¶
Values in bold differ from the HandoverLab defaults.
| Key | Value | Source |
|---|---|---|
layout.kind |
street_grid | TR 37.885 Annex A (urban grid) |
layout.blocks |
[3, 3] | TR 37.885 Table A-1 (minimum 3 x 3 blocks) |
layout.pitch_m |
[433, 250] | TR 37.885 Annex A (433 m x 250 m) |
layout.street_width_m |
20 | TR 37.885 Annex A (20 m) |
layout.site_spacing_m |
100 | assumption (dense small cells along the streets; TR 37.885 Table 6.1.3-2 has 500 m macro sites in the urban grid) |
layout.site_offset_m |
9 | assumption (sites on the pavement) |
layout.sites |
none | regular placement along the streets |
radio.carrier_ghz |
10 | assumption (upper mid-band, 7-24 GHz) |
radio.bandwidth_mhz |
200 | assumption |
radio.tx_power_dbm |
35 | assumption (small cell; TR 37.885 Table 6.1.1-2 has 43 dBm for its macro sites) |
radio.bs_gain_db |
20 | assumption (beam gain, no beam management) |
radio.ue_gain_db |
0 | assumption |
radio.noise_figure_db |
7 | assumption (typical UE noise figure) |
radio.isolation |
0.3 | assumption (mean-to-peak gain of an interfering data beam) |
radio.bs_height_m |
10 | TR 38.901 Table 7.4.1-1 (UMi: 10 m) |
radio.ue_height_m |
1.6 | TR 37.885 clause 6.1.2 (urban option A: 100 % vehicle type 2, antenna height 1.6 m; since 2.1.0, until 2.0.0 1.5 m) |
radio.pathloss |
umi_street_canyon | TR 38.901 Table 7.4.1-1 |
radio.shadow_los_db |
4 | TR 38.901 Table 7.4.1-1 (UMi and UMa LOS: 4 dB) |
radio.shadow_nlos_db |
7.82 | TR 38.901 Table 7.4.1-1 (UMi NLOS: 7.82 dB) |
radio.shadow_decorr_m |
10 | TR 38.901 Table 7.5-6 Part-1 (UMi: 10 m LOS, 13 m NLOS; the LOS value is used for both, see the limitations) |
radio.shadow_site_corr |
none | unset: uncorrelated between sites, TR 38.901 clause 7.5 step 4 (radio.channel_detail simple: 0.5) |
radio.place_share |
1 | assumption (blockage tied to place) |
radio.clutter_los |
true | TR 38.901 clause 7.6.3.3 (spatially consistent LOS state), applied on top of the building geometry |
radio.los_corr_m |
50 | TR 38.901 Table 7.6.3.1-2 (LOS/NLOS state, UMi and UMa: 50 m) |
radio.time_var_db |
1.5 | assumption (moving blockers) |
radio.time_var_tau_s |
1 | assumption |
radio.l1_error_db |
1 | assumption (error of one L1 RSRP sample) |
radio.penetration_db |
0 | off by default; TR 38.901 clause 7.4.3.2: 9 dB in a standard car |
radio.penetration_sd_db |
0 | off by default; TR 38.901 clause 7.4.3.2: 5 dB in a standard car |
radio.energy_p0_w |
56 | EARTH model, micro base station (Auer et al. 2011, Table 2): 56 W |
radio.energy_slope |
2.6 | EARTH model, micro base station (Auer et al. 2011, Table 2): 2.6 |
radio.map_res_m |
1 | numerical setting |
protocol.step_s |
0.01 | numerical setting |
protocol.l1_period_s |
0.04 | assumption (L1 sample period) |
protocol.l3_k |
4 | TS 38.331 clause 5.5.3.2 |
protocol.label_period_s |
0.2 | numerical setting |
protocol.report_interval_s |
0.12 | TS 38.331 reportInterval (ms120) |
protocol.qout_db |
-8 | TR 36.839 (Qout -8 dB) |
protocol.qin_db |
-6 | TR 36.839 (Qin -6 dB) |
protocol.qout_window_s |
0.2 | TS 38.133 (evaluation period, 200 ms) |
protocol.qin_window_s |
0.1 | TS 38.133 (evaluation period, 100 ms) |
protocol.n310 |
1 | TR 36.839 |
protocol.n311 |
1 | TR 36.839 |
protocol.t310_s |
1 | TR 36.839 (1 s) |
protocol.prep_s |
0.05 | TR 36.839 (50 ms) |
protocol.exec_s |
0.04 | TR 36.839 (40 ms) |
protocol.reest_s |
1 | assumption (1 s outage); TS 38.133 6.2.1.2.1 bounds the delay by 50 ms + cell identification (FR1: 200 ms known, 800 ms unknown cell, Table 6.2.1.2.1-1) + system information + PRACH; TR 36.842 Table E.1-2 uses 250 ms |
protocol.cho_recovery_s |
0.4 | TS 38.300 clauses 9.2.3.1 and 9.2.7 (recovery into a CHO candidate; assumption 0.4 s) |
protocol.pingpong_s |
1 | TR 36.839 (minimum time of stay, 1 s) |
protocol.cfg_loss_as_failure |
false | check mode only |
protocol.lm_load |
none | off by default: link monitoring sees the load of the data channel (calibration option) |
protocol.lm_load_per_ue |
0 | off by default (calibration option) |
protocol.exec_can_fail |
true | TR 36.839: the execution fails when the target is below Qout |
protocol.rlm_holdoff_s |
0.2 | 0.2 s since 2.0.0: an interpretation of TS 38.133 8.1.2.2 (evaluation over the last T_Evaluate_out, 200 ms in FR1) on a newly joined cell |
traffic.services |
5 entries | TS 23.501 Table 5.7.4-1 (5QI); thresholds are assumptions |
traffic.se_max |
7.4 | assumption (spectral-efficiency cap) |
traffic.hotspot_share |
0.25 | assumption |
traffic.hotspot_load |
[0.55, 0.85] | assumption |
traffic.normal_load |
[0.05, 0.25] | assumption |
traffic.load_tau_s |
0.2 | assumption |
traffic.rate_scale |
1 | assumption |
traffic.label_load |
1 | assumption (all cells transmit for the label) |
traffic.model |
fixed | fixed: constant service rates (the model of 1.0) |
traffic.period_s |
0.02 | periodic model: 20 ms, as VoIP |
traffic.packet_bytes |
100 | periodic model: assumption |
traffic.ftp_file_bytes |
500000 | FTP model 3 (TR 36.872 Annex A.1) with 0.5 Mbyte files (TR 38.802 Table A.2.1-1; TR 38.821 Table 6.1.1.1-7) |
traffic.ftp_rate_hz |
0.1 | ftp3 model: assumption (file arrival rate per user) |
mobility.users |
40 | assumption |
mobility.profile |
v60 | TR 37.885 clause 6.1.2 (urban option A: 60 km/h in all lanes) and Table A-1 (2 lanes of 3.5 m per direction): profile v60 (since 2.0.0) |
mobility.groups |
none | profile |
run.duration_s |
120 | numerical setting |
run.warmup_s |
20 | numerical setting |
Known limitations¶
- Small cells on UMi along the streets: TR 37.885 itself has 500 m macro sites with UMa in the urban grid (Tables 6.1.3-2 and 6.2.1-2); only the road geometry and the turning probabilities are TR 37.885's.
- Sites stand 9 m from the street centre line, so users pass closer than 10 m to a site; the path loss is evaluated at 10 m there (radio.pl_min_distance_m, the lower end of the UMi range 10 m <= d2D of TR 38.901 Table 7.4.1-1; since 2.0.0).
- Received-power level only: no fast fading, no link-level physical layer, one beam gain and one isolation factor.
- TR 38.901 UMi parameters are used at 10 GHz; the model's validity in the 7-24 GHz range was re-examined in Rel-19.
- The failure model is not calibrated in absolute terms; read failure rates relative to each other.
- The LOS state of a link is LOS only if the buildings leave it clear and the spatially consistent LOS variable of TR 38.901 clause 7.6.3.3 is below the LOS probability of Table 7.4.2-1; the share of LOS links is therefore lower than Table 7.4.2-1 gives (which
handoverlab verifycompares only for the links clear of buildings). - One shadowing decorrelation distance, the UMi LOS value of 10 m, also for the NLOS links (TR 38.901 Table 7.5-6 Part-1: UMi LOS 10 m, NLOS 13 m); LOS and NLOS links share one unit shadowing realisation scaled by the LOS or NLOS standard deviation, so the shadowing keeps its sign when a link changes state (TR 38.901 gives separate LOS and NLOS parameters, Table 7.5-6).
- A vehicle keeps a lane offset drawn at the start, on either side of the street centre line, through turns: it may drive in a lane of the opposite direction (TR 37.885 Table A-1 has 2 lanes in each direction).
- The number of vehicles is set for run time: TR 37.885 clause 6.1.2 places vehicles with a gap of max(2 m, exponential with mean speed x 2 s), which gives hundreds of vehicles in the grid; the interference load of HandoverLab does not depend on the number of users.
- The radio map of 76 sites and 0.2 million street pixels takes some time to build (about 17 s on a modest machine, once per seed).
Reference results¶
- Radio statistics of
handoverlab verify(path loss, LOS share, shadowing standard deviation and correlation) on a grid with the same radio settings. - Regression against the bh6 prototype on the 2 x 2-block version of this grid (tests/test_regression_bh6*.py).